Mahiru Hīragi

"Everyone’s path is the same. In the end, we all die. Humans are weak. 'What is the point of living?' 'Are we here for a reason?' Time passes before we know it. Too fast for us to waste it asking such foolish questions. So, how do we live during that brief span? What path do we choose? We’re going to die either way. Do you really think taking the long way there changes anything? Ha."

- Mahiru to Guren

Mahiru Hīragi (柊 真昼) was the older half-sister to Shinoa Hīragi and love interest of Guren Ichinose. She is a central character in both the Seraph of the End: Vampire Reign  manga series and the Seraph of the End: Guren Ichinose: Catastrophe at Sixteen light novel series.

Mahiru was from the prestigious Hīragi Family, and next in line to become head of the clan; however, as a namanari, she eventually turned into a demon, and ended up being sealed within Guren's sword, becoming a Cursed Gear called Mahiru-no-Yo.

Appearance
In the light novels, Mahiru is described as a beautiful young girl. She has long ashen hair with short sidelocks and amber eyes. Shinoa Hīragi has commented that her half-sister was taller and way more voluptuous than herself. When she was a namanari, Mahiru displayed no distinct physical features that showed the demon was in control except for a red glint in her pupils that rarely showed. After becoming a vampire, her eyes became red and grew fangs.

She is usually seen with the First Shibuya High School uniform, a sailor fuku, which consists of a blouse with red trim around the collar with a grayish blue sailor-style collar which also has red trim and a similarly colored skirt with a belt. The red uniform ribbon which is thinner than normal sailor fuku is attached to the bottom right end of the collar. The school's emblem is located on the right breast. She wears thigh length grayish blue stockings and dark blue dress shoes along with it.

Human
Mahiru was a very popular member of the prestigious Hīragi Family and was famous for treating the other clans with kindness and equality. She is shown to be gentle, sweet, and charming in Guren's flashbacks, such as sharing a cake with the latter, and showing concern over the bruises he received from his brutal training; however, Mahiru is also shown to bow down to the pressure of her family, such as hiding and refusing to meet Guren when her family sent two people to interrogate him.

Her great intelligence and skill made her father favor her, but she hated the Hīragi Family. Mahiru appeared to be less cold-blooded and ruthless than her half-brothers, saving Sayuri when Seishirō beats her and attempted to strip her as she did not like picking on others. She was noted as a perfectionist, more likely stemming from having many expectations on her while doing battle with the demon born inside her. Mahiru appears to value human life more than her family, shown in her desperation to save Shinoa, who also had a demon inside her, and Mahiru ultimately took Shinoa's demon and sacrificed the rest of her humanity for her half-sister.

What's left of Mahiru's human side is often seen wrestling for control with her demonic side in the light novels. Whenever Guren is injured, such as when he sliced off his own arm to stop the spread of the demon's curse, Mahiru's human side is able to resurface briefly, crying as she desperately tries to reattach Guren's arm. She also at times desperately warns Guren not to be fooled by what her demon side says and expresses deep remorse and guilt over what she put Guren through along with also hating herself for doing it. She even went as far as to request to be killed by Guren.

Namanari
Mahiru is in this state for most of the Catastrophe light novels. The demonic side of her gradually takes more and more time in control of her body and twists her love for Guren by starting his transgression into demon hood as well. Her need for power to protect and be with Guren warps into a desire to either rule or destroy the world.

Mahiru-no-Yo laughs often and loves to mock Kureto and the other characters. She has no sympathy or compassion for anyone and is willing to ruthlessly kill anyone who stands in her path and is even cruel to them. Among the very few things that remained of her previous self was her love for Guren but even then, she is not above being cruel and be willing to harm him. Her love is also twisted so that while she will not kill Guren, she is absolutely delighted when Guren shows his strength or touches her and wants him to give in to his demon and join her. She is, however, not above showing other dark emotions whenever Guren is involved, showing cold rage when Guren coldly said he didn't gain power just to be with her and a strong sense of jealousy towards the girls who love Guren despite knowing how Guren would never fall for them as he only loves her and acts particularly cruelly due to this, along with also showing resentment at even Guren's other friends, noting that she wants him to kill all of them and actually being bitter when referring to how Guren wanted to protect both her and them. Along with that, she maintains contact with Shinoa, seeming to indicate she retains her care for her. Since the human and demonic personalities are in flux, they can be seen arguing and fighting for control when the demon puts Guren in danger.

Vampire
Mahiru's personalities no longer fluctuate, and she expresses both the haughty playfulness of her demon side and the hopeless love of her human one. She is now consumed by lust for blood, especially Guren's, and she enjoys feasting on people's blood and drinking them dry. She also enjoys battles and manipulating others to do her will.

Her human personality seems to be about as strong as her demon one, however, which manifested in her showing love for Guren and care for Shinoa as well as being much more easily angered and jealous. She gave her sister Shikama Dōji to make sure she can survive the end of the world and spared Guren despite having him at her mercy along with actually trying to protect him from her malicious experiments. While Mahiru's love for Guren made her not kill him while she killed all of his friends, this was not granted to his female friends, who was cared for Guren in front of her, much to her cold rage, and her fiancé, who made the mistake of mocking her love for Guren, earning him a particularly painful death, as she slaughtered all of them ruthlessly but at the same time she willingly told him how to resurrect them as she died. She was also genuinely touched to the point of tears as Guren proclaimed his undying desire to save her and as she died, revealed all she wanted was to have a normal life with him.

History
Mahiru was conceived through artificial insemination using the seed of Tenri Hīragi in demon-possessed women, which lead to her being born in 1996 with a demon inside of her. Eventually, when Mahiru was six years old, the Hīragis had her mother killed, so Mahiru attempted to anger them by becoming close to the Ichinose Clan, where she encountered Guren Ichinose. Shortly afterward, the two fell in love until they were violently separated for the next ten years. Three years since Mahiru's separation from Guren, her half-sister, Shinoa Hīragi, was conceived through the same demon experimentation and was born with her own demon inside her. At some point (or even earlier), Mahiru began having nightmares where the demon spoke to her from the shadows, and its voice would get louder as she continued to grow. When she learned that Shinoa was also having the same dreams as her, Mahiru tells her to not tell anyone or they would be used as experiments again.

The following year, the Hīragis selected and adopted Shinya to be Mahiru's potential mate to keep their bloodline strong, despite both of them being ten years old. Mahiru oversaw some part of Shinya's training against other candidates.

Upon meeting Shinya for the first time, Mahiru tells him she wouldn't fall in love with him as she already had someone; however, if she openly stated to her family she didn't want him, they would have disposed of him, and Mahiru still wanted to be with Guren. Hence, she and Shinya agreed that he would be her cover-up fiance until she could be with the person she loved. When Mahiru hit puberty, the demon's influence became stronger in that she continually blacked out and lose herself to desire. Not wanting Shinoa to end up with the same fate, Mahiru revived the demon curse experiments and joined the Brotherhood of a Thousand Nights to aid her in exchange for giving them info on the Hīragis. Thus, Mahiru began her research and development on Cursed Gear, and would use herself as a guinea pig to test the power of the demon weapons. At some point, she somehow extracted the demon from Shinoa and took it into herself, which sped up her transformation into a demon.

On top of turning into a demon, Mahiru saw visions of the future and even prophesied the end of the world on Christmas Day 2012 as God's punishment against human ambition for meddling with the taboo.

Events of 2012


Ten years after separation, Mahiru and Guren would cross paths again at First Shibuya High with the latter finally seeing the former give the freshmen address. At the school, Mahiru and her brothers are the most popular and respected by the student body due to their power and family status. After Shinya puts Guren in the nurse's office, Mahiru comes to visit him and reconnect after many years, but he treats her coldly and even mockingly congratulates her for being bethroted to Shinya, leaving her hurt and frustrated over Guren's change.

During the qualification exams, she saves Sayuri when Seishirō severely beats her and begins to strip her but coldly tells Guren she refuses his gratitude, seeing him as being weak for not fighting for her anymore, and leaves with a dark look on her face, but not before she hears Guren tell his attendee they did well as if to mock her, further infuriating her. Sometime later, the Brotherhood of a Thousand Nights attacks and kills many students and teachers. While fighting Saitō, Guren and Shinya learn that Mahiru betrayed the Hīragi Family by joining with the Thousand Nights. Mahiru then turns up when Guren states that he isn't gaining power just for her and tells Guren to not say such a thing when he doesn't mean them with cold anger, unleashing a strong killing intent, and attacks Guren with a black katana. Although Guren is able to successfully fight her off with his superior sword skills, Mahiru's own fighting prowess and her superior physical abilities slowly overwhelms Guren.

She then reveals that her sword is a cursed gear, a demon-possessed weapon that she and the Thousand Nights were able to successfully create and, with the combination of the Thousand Nights and Hīragi magic, was even able to make contracts with bind high-ranking demons. She tries to convince Guren to join her when she suddenly stops mid-sentence and becomes pained. She is able to get out to Guren that the demon has possessed her and that the cursed gear experiment is actually a failure before denying that there's anything wrong.

The sword then begins affecting her right arm which prompts Saitō to tell her that they need to go. Angered by the dressed man, Guren lunges at Saitō only for Mahiru to intercept his blade which cuts his sword, Kujakumaru, in half. Mahiru gives Guren one last chance to come with her which he refuses as his quest for power is different from hers. She then tells him about the apocalypse happening on Christmas and will meet again when the world comes to an end. Before making her leave, Mahiru tells Guren she loves him and promising that she will be waiting for him when he needs her again.

During their investigation of Ueno Zoo, Guren Squad battles a tiger-like creature that was made with genes from the Horsemen of the Apocalypse. When the squad was about to retreat after due to Guren's wound, Mahiru turns up and knocks Mito, Norito, Sayuri, and Shigure unconscious in moments. Shinya was able to avoid her strike before Mahiru was able to grab him by the neck and choke him to unconsciousness. She tells Guren that she plans on betraying the Thousand Nights as her loyalties lie wherever there is power. When Guren asks where that power is, Mahiru says that it is in depravity and madness which lives deep in the heart and that Guren should follow that path as well.

She then thrusts the black katana into the ground with its curse affecting Guren. Mahiru encourages him to take the sword to slay the chimera before stepping back to watch. When Guren reaches for the sword, Mahiru suddenly cries out to him to stop and not lose his humanity before telling herself to be silent and hitting herself in the chest. This stops Guren momentarily when he asks Mahiru which one is the real her, which leads her to ask if it had anything to do with his choice.

After that, Guren takes the cursed gear which causes a demon to sprout inside him. Mahiru becomes ecstatic when Guren makes quick work of the chimera and goads him into killing his friends and joining her. Guren was about to do just that when his other hand used his sword, Hoarfrost, to severe the lower part of this arm that was holding the demon blade. Mahiru quickly gets that limb and holds it tightly to Guren's arm so the demon's regenerative ability can reattach the arm. Mahiru then becomes desperate and becomes tearful when the regeneration process isn't working fast enough. Guren tries to convince Mahiru that there could be another way and for her to stop this cursed gear research, only for her to reject him and getting her offer rejected in return. During their talk, Guren's arm fully reattached itself, which Mahiru confirms that the demon has tainted a part of Guren's soul and promises that he will fall just like her.

She then rushes over to claim one half of the chimera's corpse but notices that a well-dressed vampire is also there. She immediately attacks him, but even with the demon's power, the vampire is able to withstand her Cursed Gear. Mahiru identifies him as a vampire noble, which he confirms and introduces himself as Seventh Progenitor Ferid Bathory. He resumes their fight, in which Mahiru is defeated along with Guren, and Ferid proceeds to take the other half of the chimera with him. Mahiru demands to know what he is doing here, and Ferid answers that he is investigating what he has heard about humans researching the forbidden. Knowing that she stands no chance against the vampire, Mahiru sheathes her sword and reveals to Guren that the Cursed Gear can become even more powerful, but doesn't have enough time to explain. Reminding Guren that he will fall like her, Mahiru picks up the other half of the chimera just as a Thousand Nights helicopter arrives.

Just when she was warning Guren to leave, Mahiru notices dozens of Fuda were placed on the ground to form a barrier and realized that Shinya was awake the whole time when she was revealing her intentions to Guren. Determined to capture her, Guren lunges at Mahiru while Shinya uses the Fuda to retrain ensnare her legs, which Mahiru breaks through with ease; however, Guren surprises her by slicing off a piece of the chimera. She tells Guren that she can't allow the Hīragis have the chimera, but allows Guren to take it once he promises it won't be going to them and because she is betraying both sides. Hearing Guren promise that he will be catching up to her, Mahiru tells him that she will be waiting before leaving.

Later, Kureto pretends to torture Shinoa while interrogating Guren. Mahiru sends Kureto a message telling him to do as he pleases, and tears briefly form in Shinoa’s eyes. Kureto sends the IP address to Guren, and Guren sends a message to Mahiru. Mahiru calls Guren, and he puts the phone on speaker. Guren, Shinoa, and Kureto all speak to her. Shinoa says everything went as Mahiru predicted. Mahiru twists the conversation and repeatedly states that all of the events occurring since the first Catastrophe volume are his doing. She reveals the special ops he sent after her just now are already dead. A student rushes in and reveals that this entire conversation was just broadcast over the whole school.

After Kureto releases Guren and Shinoa, Mahiru calls him again. She says she only wants to hear his voice and says the demon was in control before. They establish a rendezvous at 5:30 p.m. in apartment 501 located fifteen minutes from Ikejiri-Ohashi Station. Guren reads about the demon experiments going on in Mahiru and Shinoa. The research notes reveal Mahiru and Shinoa’s origin and how the demon will drastically increase when Mahiru hits puberty. To prevent Shinoa from suffering the same fate, Mahiru joined the Thousand Nights and used herself as a test subject.

Mahiru does not arrive until 7 p.m. Although she tells Guren he cannot save her, he insists he can, and they have sex that evening. She tells Guren that he wants to protect his own comrades rather than her. Mahiru reveals she now has both her demon and Shinoa’s inside her body, which has sped up the rate of her degeneration. She shared part of the demon with Guren in order to remove all of the demon from Shinoa, so he will eventually become a demon as well. When he asks to fight by her side, she tells him there is not enough time and reveals the Apocalypse occurring that Christmas.

The vampire who chased Guren and Shinya the previous night enters through the balcony and greets Mahiru, but Mahiru calls upon Asuramaru and quickly kills her.

Mahiru reveals she fabricated information to set the Hīragi House and Thousand Nights against each other. Guren says he refuses to let her give up her humanity before Mahiru jumps out the window. When Guren learns that the Thousand Nights is attacking the school and leaves shortly afterward, he comes across a running motorcycle and a demonic sword waiting for him in an alley that was presumably left behind for him by Mahiru.

Mahiru has an illusion over the whole school and is responsible for instigating the conflict between the Hiragi and the Thousand Nights.

Mito, Shinya, and Goshi play video games at Guren’s apartment until Mahiru shows up. Guren attacks her causing them to fall from the twenty-fifth floor. Mahiru stops her fall by using her sword while Guren is badly injured but recovers.

Mahiru visits Yuichiro Hyakuya, who is being experimented on and abused by the Hyakuya Sect. She asks him about his reason to live and if he has no right to live if he is a demon. If parents tell their child to die, Mahiru asked Yu whether that child would have no choice and what law says that. Since his mind has not broken from his experiences, she tells him he will find an answer one day. A researcher says he will erase all memory of this conversation from Yu’s mind. She asks about receiving one of the Hyakuya orphans to experiment on with cursed gear.

Kureto calls Mahiru and tells her in explicit detail about how he will torture Guren, but she only laughs and says she is going to Kyoto. Mahiru visits one of the Hyakuya Orphanages with the pseudonym, Miyuki Yamada. She chats with Akane Hyakuya and realizes she has a crush on Mikaela Hyakuya, one of the subjects with a body well-suited to experimentation. She “adopts” a child named Junji Haiyama before taking him to a van on the opposite side of the street, killing the driver, and knocking Junji unconscious. She enters the freeway but is attacked by vampires. She fights them, but they cause a large car pile-up. The vampires capture Mahiru and take her to Kyoto.

Mahiru is tied to a cross deep within Sanguinem and is being tortured. Krul Tepes asks her if she is ready to talk and reveals the date is already December 20. Mahiru summons Shikama Doji and breaks free. Krul asks Mahiru about Ashera Tepes, but Mahiru only laughs.

On December 2, Mahiru leaves Sanguinem as a vampire sired by Krul. Saito gives her a ring to protect her from sunlight, but she attacks him with Shikama Dōji. Mahiru knocks out a human woman and drinks her blood, noting that it tastes different depending on the age and sex of the human and that the blood turns bad once the human dies. Mahiru then returns to Tokyo.

On December 10, Kureto sends in Guren and his gang to take care of students that have become possessed by demons at the school.

Guren arrives first and knocks out one demon-possessed boy when Mahiru appears and applauds Guren’s strength. She admits this was her doing and asks about the experimentation on Asuramaru. She says a human must be modified in order to use a Black Demon, but the current success rate is less than 20%. Guren says he wants to protect both her and his friends and asks that she surrender, so he can extract the demon from her. She throws down Shikama Dōji and instructs him to give it to Shinoa in order to protect her. The rest of the group arrive and attack Mahiru, she drinks Guren blood and expresses how delicious it was and escapes.

Guren calls Mahiru and says he will betray the Hīragi and join her. She laughs.

On December 23, 2012, during the call with Mahiru, Shinya took out a mobile phone from his chest pocket and connected it to the audio system of the minivan they were in so that everyone could hear the sound. Mahiru apologizes to Guren telling him she is too motivated by another invitation 2 days before Christmas and it's too late, Guren tells her if there is a third party involved which Mahiru tells him if he is concerned and telling him that she loves him and romantically likes him. Mahiru being happy that knowing is the call being tapped, Mahiru kept on laughing hearing their conversation about betraying the Hīragis and kept telling Guren that she loves him, she tells them most of the clans are planning a revolt, when asked by Guren where they could meet she answers if she loves him now, Guren asks again but she tells him she is busy and it's a secret since she will kill Kureto when Guren asks how can they meet, Mahiru replies after killing Kureto she will contact him, saying to Guren try to survive, before the call ends.

Mahiru finds out Kureto in First Shibuya high Kureto spots Mahiru and attacks her using Raimeiki lightning, she dodges all his attacks, as she overpowers him easily, Mahiru laughed Kureto regains his composure swung his sword against her neck though hitting his face to escape, crushing his left eyeball and damaging his brain as Mahiru gains the upper hand. She taunts Kureto, however Kureto eye is healed and she notices 200 snipers aimed at her knowing it's just an illusion trying to escape but Kureto holds her hair, he uses a lighting bolt from Raimeiki which damaged her severely, burning her internal organs as she wonders if she will die, a laughing Kureto says it worth it telling her it's his job killing her ordering the 200 snipers to finish Mahiru.

However Mahiru manages to recover broke his neck and threw him, knowing that all the 200 snipers are charged with cursed bullets, Mahiru reveals her first-class vampire weapon she slices all the bullets easily. Much to Kureto surprise even though he was at Mahiru mercy he was confident that the snipers would aim at her laughing, she brushed it off as she used her own curses which countered Kureto using her own illusions to perform small tornadoes and a hundred monsters. In desperation to defeat Mahiru he ordered his soldiers to kill her but since she is a Hiragi they would commit a crime. Mahiru overpowered him completely if not for Raimeiki he would've died, knowing killing her is an impossibility as Mahiru laughs.

Mahiru informs him about the Hīragi revolt and asks her if he is going to kill her or if she is buying time she tells him that he is an important brother to be killed adding that she will take full responsibility for the Hīragi fall and asks him why does the Hīragi have such power, when asked why does she even fight her response the world will end and it's definitive, she doesn't respond when he tells her who made such decision, before leaving she told him to treasure Guren.

She phones Guren at 22:35 telling him to become a psychic so he can see the future and prevents his friend deaths but Mahiru tells him even if the world would end. Guren tells her he betrayed everyone just to be on her side, which if she should reward him and he has a painful life as Guren wonders where she is by hearing the background sounds wanting to protect her however she laughs and says he can't, he tells her why would she call him then she laughs again when he thought that he wanted to protect her and hear her voice, she tells him that this is just his hypothesis and he actually wants to see her. When Guren was protecting his friends she laughs telling him if he's protecting another woman. She decides to tell him her whereabouts telling him the laboratory in Ginza that the Hyakuya Sect once owned, baiting Guren and lying to him before ending the call she wanted to hear Guren's voice and telling her he will come to Ginza she thanks Guren and telling him she loves him and she's waiting for him, Guren ends the call, as she had a sad expression.

On December 25, Kureto revealed Mahiru location to Guren location in an underground laboratory that spreads to Shinjuku Central Park. It was the research institute of the Thousand Nights. As Guren and his friends arrive to confront her stopping her ritual that would cause destruction to the world, as the group wonders if they can stop Mahiru or save her. They form a formation to defeat Mahiru. Mahiru was drinking the blood of humans killing many humans and leaving nearly 20 corpses. As much as she is happy to see Guren again, Guren came to save her telling him its impossible anymore. Despite the group combination they couldn't scratch her and immobilizing their formation, as the group struggles, Mahiru overpowers them easily while laughing, Guren tells her he came here by Kureto request though she ignores him and telling him to worry about his friends recovery instead, Guren saying if he hadn't had friends he would never be able to reach here and she tells him to kill her since that's the only way to save her, Guren refuses to do so and she asks him the meaning of life then.

As his friends recover forming another formation, Shinya mockingly telling her the truth about her obsessed affection for Guren and telling her to accept her own weakness since it's still not too late as Mahiru listens, this angers her silencing him and stabbing him piercing his chest and torturing him more by keeping her arm pierced deeper into his chest despite Guren attempt to save him begging Mahiru to stop. She asks Guren again the meaning of life but Guren was losing his sanity by Noya consumption and devastated at Shinya's death.

Asking Guren if he hates her now which he agrees calmly but he denied when asked if he is going to kill her, wondering why since she done horrible things to him even killing all his friends telling her if would ever let his anger out his friend Shinya would be angry although Mahiru tells him the latter is dead, Guren responds even if he's dead they can win as his destiny will lead him. She tells Guren that he is weak and death is simple for him, as Guren threw away Noya knowing full well he can't win using it against Mahiru since Mahiru abandons her weakness and always seeks the strong way out which she repeated multiple times, even though she tells Guren she didn't throw away her weakness as she views Guren strong telling him to save her. When Guren had enough of this since everyone is dead, that even if that it is his wish it has been granted.

Taking her phone looking at only few hours left till the end of the world, she tells Guren about the forbidden magical experiment the Seraph of the End and what will happen if it is activated and all the information Saito told her she explains the Seraph of the End that it is the controller of God punishment, Guren denies the existence of God but Mahiru told him if there were a god there must be a reason to have created a terrible world. She tells him that heavenly punishment is such an amazing power but manipulating with it any further would be bad.

After picking up Noya and welcoming it back, Guren asks her one last time to save her then with a crying face telling him it's impossible, stabbing herself using Noya in the heart which confuses a panicked Guren as he tries pulling the sword out she warns him that she integrated with Noya into her heart while laughing as she weakens, Guren embraces her as she starts suffering from the curse and after Guren wants to know her desire she simply wanted to be an ordinary girl. The curse spread most over Mahiru's body worrying Guren about her death and told him it was her plan to die. She tells Guren about her experiment and due to her birth the heavenly punishment was solely for her and due to her mother being mixed with a demon, Shinoa and herself made countless sacrifices telling him this planned.

Noya eventually dyes most of her body with the curse with Guren lamenting himself. She tells Guren with her dying words that she touched the taboo he control still crying happily at Guren and coming here with his friends to confront Mahiru wasn't part of the plan and what would happen if the Seraph of the End is triggered and how to activate it. Noya curse eventually spread all over Mahiru.

Post-Shinjuku Arc
When Shinoa goes and meet Guren at the lab underground he mentions her sister Mahiru invented Cursed Gear, and that sacrifices are necessary. There is eventually a distant figure of her in a brief flashback.

Guren reveals her demon form during a fight with Yu. After hearing Guren summon his demon by calling out her name, Shinoa holds her scythe at Guren's neck. She reveals that her weapon specializes in long-range combat and consequently stands no chance against a melee fighter like Guren at that range. Guren calmly says he would let Shinoa kill him. Shinoa asks him if that is his way to atone for killing her sister, Mahiru. She asks if she is in his sword since she heard him call her name. Guren says that Mahiru is already gone since she turned into a demon and saved the world by completing Cursed Gear. Shinoa laughs, stating that Mahiru was never one to care about the world because she loved him. She longed to be with him since they could never be together and became obsessed with demons.

After discussing the events of 8 years ago, Shinoa says that if Mahiru hadn't completed the development of Cursed Gear, humanity would have perished. Her half-sister, who was just a girl in love became something like a Messiah. But then she was killed when she became obsessed with her research and became a demon. She continues saying, the one who killed Mahiru was the person who used to be her lover, him, Guren.

Shinoa asks him if Mahiru is together with him inside his sword, stating that he is being possessed by her. Guren asks her if they ever got along. She explains that she was not close with her sister because Hīragis are raised without knowing familial love.

Shinoa asks if making use of Yu was one of Mahiru's orders and asks if her half-sister or the demon for lack of a better word inside his sword is ordering him. She then asks him to stop what he is doing if his goal does not benefit Yu.

Guren tells her that Mahiru is dead and isn't coming back. He says that the demon inside his sword is under control so he isn't being possessed by her. But Shinoa doesn't believe him.

Osaka Arc
After the fight with Ky Luc, Asuramaru wanted to know what trauma has led Yu to be who he is, the demon sees Mahiru in a flashback. In it, she talked with a traumatized eight-year-old Yu, who was being held by the Brotherhood of a Thousand Nights.

Shibuya Arc
Kureto mentions Mahiru as the reason why Shikima Doji targeted Shinoa, as she is her younger sister. According to Guren, he shares that it was in fact Mahiru who found Yu and that before she died she made connections with a second progenitor involved with the Hyakuya Sect: Saito. Whether Mahiru chose Saito to take action against the first progenitor that was going for her is contemplated by Kureto in his discussion with Guren and Shinya.

When Mahiru-no-Yo is struck by Guren's sword during the assault on Shibuya by the Hyakuya Sect, the joint being of Mahiru-no-Yo is separated back into Noya and Mahiru. She appears in pain as Noya breaks out before laying motionless In a spirit like state, Mahiru bears the chest wound as she floats before Guren and tells him to not say much in his demon state. With Noya offering the opposite advice, Mahiru swings the sword to Noya's mouth and orders him to be silent. She faintly smiles in silence at being recognised by Shinya. She joins Noya, Guren as a demon who is supplementing his power with chains (together referred to as Mahiru-No-Yoru) in combining their energies above them.

Invisible, the spirit of Mahiru joins Guren in arriving at where Shikama Doji battles with Saito. She is able to halt the scythes sent by the first towards herself, Noya and Guren. Mahiru tells Shinoa to hang in there as she will rescue her. She voices her surprise at Saito betraying them, using his fangs intending to bite Guren to acquire the evil keys and gain their powers. With the help of Ferid using Jigenso, Mahiru, Noya and Guren all acquire an evil key each then they surround Shikama Doji with a sinister power entrapping Shinoa. She catches Shinoa in her arms after Shikama Doji leaves her body. Saying her name, she manages to wake her and is recognized, then stays alert. Later she finds Mika debating his next move concerning Guren and appearing behind him, she answers his question that saving Yu is way beyond him and returns his sword strike with one of her own. Complementing his speed, she is aware that he is Krul's vampire and when asked who she is, she joyfully introduces herself to Mika by stating she is everybody's favorite lovely idol. Mahiru remembers now is not the time, she has to hurry and overwhelm him while the life-absorption barrier is still active. Charging at him whilst asking if that is okay, her sword attacks are avoided by Mika and she expresses worry at Mika's weapon coming close to her. Making use of shikigami-talismans, Mahiru appears behind Mika cheerfully stating she has got him, he loses and goodbye. With her sword avoided, she notes he did not lose and remarks that Mika really is fast. Mahiru does feel he lacks skill and detonates several spell tags, telling each one to explode and they do so across the top of buildings, laughing as she does this. With Mika forgetting her to save Yu, Mahiru supports this decision, stating aloud for Mika to run off and save Yu. Mahiru appears in the sky in front of both Yu and Mika, and greets Yu happily mentioning it has been forever. With Yu not knowing her, she asks if he does not remember her from the prison when Yu was five and called demon spawn. Reminding him that his own parents tried to kill him, a lone monster all lost and alone with no reason to live, Mahiru asks him if he has found a new reason. Triggering some of Yu's memories, a flashback is shown back when she visited Yu as a child in a prison then heard that he was demon spawn and a monster where everyone would be happy without him in the world. Mahiru questioned whether monsters are allowed to live too, and even if parents tell their child to die, does that child have no choice. Mahiru queried what law says that before being informed by researchers that it is useless talking to that test subject as they will manipulate his memories either way. In the present time as Yu remembers they met, Mahiru magically produces a glimmering stream of spell tags from her hand. She smiles in silence at hearing Yu answer her question, that he had found a new reason to live in Mika. With Yu and Mika evading them, Mahiru tells Guren she has planted wards all over, questioning if he wants her to cut off their escape route. Instructed to get back inside him, Mahiru blushes after interpreting the message carnally before remarking that Guren is so lewd. Encouraged by Noya's comment, Mahiru asks whether she and Guren get to make out in public. As Mahiru shows a happy face and blushes even more, she obliges with his order to return to the sword. As Guren faces Yu and Mika, Mahiru alerts Guren that they are coming. She is called upon to auto-block the invisible swords that Yu has in store for them.

Mahiru is later seen with Guren and Noya, she hears the Death Wail faintly commenting to Guren that it's finally beginning, whom confuses Noya when he was experiencing the pain in his ears of the Death Wail shout. She laughs a little at Noya whom he keeps shouting at both Guren and Mahiru plans. Mahiru tells Noya not to worry questioning him that he does like human desires and injects Noya with a shot, as she grows horns simply telling him to eat her desires and grow even stronger. She senses fear from him strangely and informs him if demons get scared and if they are they will end up getting eat up by humans. When Noya questions her and Guren what as to what they are after, She simply answers love. Guren orders her to end this up, Mahiru then injects Noya with a shot that knocks him unconscious. She and Guren then watch as Mika turns into a Black Demon.

Natural Abilities
As a human, Mahiru was an exceptional fighter, being the most prominent candidate to be the next leader of the Hiragi Clan, being stronger than even Kureto, which he openly admits. The most skilled of her class in fighting skills, her movements were acknowledged by even Guren to be quick and graceful. He noted she could potentially be even more skilled than Shinya, who's considered one of the best fighters in the school, which was further supported by how she was able to rather easily defeat him when they first met. She nonchalantly blocked Seishirō's attack on Sayuri with one hand while the other held the girl and easily intimidated him to submission despite his arrogance. She has also proven herself to be capable of easily fighting on par with and pressuring Guren in a sword fight.

Noted by Kureto and Shinoa, Mahiru was also intelligent and a genius. She's one of the early pioneers of the Cursed Gear, which is essential for mankind's survival ever since the Apocalypse. At a young age, Mahiru is able to extract the growing demon inside Shinoa, but at cost of her own humanity. She is credited for completing the Cursed Gear and hailed as a hero. In Catastrophe, upon losing her humanity right after transforming into a vampire, Mahiru noted to herself that she has finally managed to obtain strength, which is equal to a third progenitor-like Krul Tepes. Whereas a vampire's power is dependent upon both age and lineage, it's unknown if Mahiru was really as powerful as she believed to be. This was because of Mahiru's was still young being in her late teen, in comparison to Krul, who has lived for a really long time, though she expressed strength far surpassing Guren and Kureto even with Kureto's power augmented by Raimeiki. Guren admitted himself he is no longer a match for Mahiru.

Unlike Mikaela, who also became a true noble vampire by Krul, Mahiru doesn't seem to have a first-class vampire weapon in possession, but still used the demon weapon, Shikama Dōji with its forms and abilities instead. Though it is later revealed that she possesses her own a first-class vampire weapon as shown when she fought Kureto. Upon discarding it, Mahiru can truly unleash her potential power as a true noble vampire, which is greater than that of a demon she originally became before the events of Seraph of the End occurred. Even so, despite the tremendous power she has greatly attained from Krul, it was still not far from enough to even scratch the second progenitor Saitō and defeat him. However, she was still effortlessly capable of dispatching the entire Guren Squad, as Mahiru was able to pierce a hole through Shinya's chest and lift him nonchalantly with the hand impaling him, killing him before even the squad noticed her, and killed the rest of Guren friends easily.

Equipment

 * Talismans: Although not often making use of talismans, Mahiru has also proven to be considerably skilled in using them and could skillfully use illusions with them. Her skills are so great that in addition to being able to easily trap Shinya, a notorious master of using magic in his own right, when they were young, in an illusion and then place and activate an exploding spell-tag, along with also trapping Guren in an illusion rather easily, she could simultaneously use more than 100 curses, a feat that astonished Kureto, as he can only use up to 7 while Mahiru can use more than 100 curses,Catastrophe Book 3 - Mahiru wielding Asuramaru.png using them to perform small tornado's and a hundred monsters in a battlefield in the same matter as Norito Goshi to easily counter Kureto's illusions completely.

Cursed Gear

 * Asuramaru (阿修羅丸): Asuramaru is a possession-type demon weapon of the Black Demon Series. It resides inside a black sword that Mahiru once used. Whilst in use, the blade developed a thick green aura. She could call upon Asuramaru to fully use its power to attack opponents.


 * Shikama Dōji (四鎌童子): A manifestation-type demon weapon from an unknown series. It is strongest at mid-range. His primary ability is to detect anything that comes within the attack radius of his scythe.

Book 1

 * "When we get older… do you think the two of us could get married? We could be together, forever, just like we are now."— Six-year-old Mahiru to Guren, Prologue, Page 13


 * "You shouldn’t have pulled your bandages off like that."— Mahiru to Guren when checking on him, Chapter 4, Page 74


 * "I’ve changed too, Guren. I decide who I see now, and what I do. It’s a Hiragi’s duty to look after the clans under our command."— Mahiru to Guren, Chapter 4, Page 75


 * "You were more rough-and-tumble as a child. When did you learn to say such flattering things? I don’t care if it’s flattery. I’m just happy to hear you call me beautiful."— Mahiru to Guren, Chapter 4, Page 76


 * "…do whatever I want? I don’t have any interest in making father happy and I never have."— Mahiru to Seishirō when she saves Sayuri, Chapter 6, Page 125


 * "I don’t want you to apologize to me. Especially not this weak you, who can’t protect the girls in his life."— Mahiru to Guren after saving Sayuri from Seishirō, Chapter 6, Page 125


 * "Impressive! You really have become strong, haven’t you, Guren? Was it all for my sake?"— Mahiru to Guren, Chapter 7, Page 153


 * "I see… All I ever wanted was to be with you again, Guren. That’s why I grew stronger."— Mahiru to Guren, Chapter 7, Page 153


 * "Ahaha. Once I began acquiring power, I enjoyed the feeling. You understand, don’t you, Guren? You’ve grown so strong, but you’re still flesh and blood. You must feel the seductive pull of power… There’s a limit to flesh and blood, though, isn’t there? To become truly powerful, you have to be willing to transcend to the next level."— Mahiru to Guren, Chapter 7, Page 154


 * "You look surprised. Amazing, isn’t it? A cursed weapon. It’s a combination of Hīragi and Thousand Nights magic. We learned how to make contracts with high-ranking demons that were formerly out of reach, and to bind them into weaponry…"— Mahiru to Guren about the Cursed Gear, Chapter 7, Page 154


 * "It’s not quite perfected…but I think we’re close. Just think of it, Guren. With a weapon like this, what is there left to fear? The Hīragis are powerless ants in comparison. Even vampires would be no threat. They think of humans as no more than mere cattle, but with a weapon like this we could kill them. It just needs to be perfected. Look at it. It’s so beautiful—"— Mahiru to Guren, Chapter 7, Page 155-157


 * "Since when did you become so high-minded? You act as if you’ve never sacrificed anything. But I have a feeling you’ve given up more than your share to gain the strength you have now. It’s a lesson we learned together, Guren. That day, on the grass, when the sky was so blue. Without strength, you can’t protect anyone. Not the ones you love, and not the things that are most precious. All that matters is power. I know that, now. And so do you, Guren… Come with me. I can give you power, Guren. We can perfect this strength together. We…we can—S-Stay away, Guren! It’s too late. Too late… The demon, it’s already possessed me. The cursed gear…our experiment… W-We failed… This isn’t me. I…I… Shut up! Shut up! No one is possessed! I just need power…more power…"— Mahiru to Guren as she starts to struggle against the demon, Chapter 7, Page 157


 * "You spared me earlier, so I guess that makes this a draw. Not that getting stabbed in the heart would actually kill me…"— Mahiru to Guren, Chapter 7, Page 158


 * "…I want to tell you something important, Guren. The truth is, this year at Christmas, the world will come to an end. The trumpets of the apocalypse will sound, and a virus will spread. When that time comes, a new world will arise. One that, more so than ever, requires power. When that time comes, I know you’ll need me once more… We’ll meet again, Guren, when the world comes to an end."— Mahiru explaining when the world will end to Guren, Chapter 7, pages 159-160


 * "I love you, Guren. That much is true. A day will come when you need me again… Until then, I’ll be waiting."— Mahiru to Guren before leaving after their clash during the attack on First Shibuya High School, Chapter 7, Page 160

Book 2

 * "Don’t try to resist, Shinya. You wouldn’t want me to slip and accidentally kill you."— Mahiru to Shinya as she jumps out to choke him, Chapter 7, Page 303


 * "My loyalties lie in the same place as yours do, Guren. Wherever there is power. Enough power that no one can ever interfere again. Enough power so that no one can keep us from the people we love, so that no one can take our freedoms away from us again."— Mahiru to Guren, Chapter 7, Page 305


 * "My loyalties lie deep in the heart, where madness and depravity live. As do yours. Don’t they, Guren? But it’s not enough. You need to sink to the same depths as I have. Why didn’t you kill that girl from the Jujo Clan a moment ago? Or that fool from the Goshi Clan? It’s what you should have done. You need more hate, more madness. Let it rush through your body, Guren, let it consume. Demons thrive on the hopes of man. In order for a demon to choose you—"— Mahiru to Guren, Chapter 7, Page 305


 * "Everyone’s path is the same. In the end, we all die. Humans are weak. 'What is the point of living?' 'Are we here for a reason?' Time passes before we know it. Too fast for us to waste it asking such foolish questions. So, how do we live during that brief span? What path do we choose? We’re going to die either way. Do you really think taking the long way there changes anything? Ha."— Mahiru to Guren, Chapter 7, Page 305


 * "You’ve got it wrong. I’m not trying to pull your strings, Guren. The decision is yours to make. But you won’t resist it. You thirst for power. You need it. You’re just like me. You’ve already fallen. You’ve fallen deep, and there’s no climbing back out."— Mahiru to Guren, Chapter 7, Page 306


 * "Ahaha! In the end, it looks like you really don’t have a choice. That creature is a chimera. It’s been altered using the genetic material of the Four Horsemen of the Apocalypse. If you don’t draw the black sword from the ground, you’ll never be able to defeat it. You’ll die. And all your little friends, lying unconscious on the ground here, will die along with you."— Mahiru to Guren, Chapter 7, Page 307


 * "That’s it. Take the power that’s offered to you. Give up your humani… S-Stop, Guren, don’t! If you do it, you’ll never be able to return… Shut up! SHUT UP! He almost did it. You… I… Shut up!"— Mahiru to Guren as she starts to fight with the demon, Chapter 7, Page 307


 * "Ha! Amazing, just as I expected! Ah…hahaha… I bet you want to kill me too. You can’t control it, can you, the impulse to destroy? You want to kill your friends here too, don’t you? You want to string the boys up by their innards, don’t you? Rape the girls and then twist their heads off their shoulders? That’s the one problem with that sword… The demon ends up possessing the wielder, turning his soul murderous and dark. Don’t worry, Guren. Killing these five should temporarily quench the sword’s thirst for blood. Afterward, we can search for a way to control the cursed gear together. If we work together, I’m sure the two of us will be able to perfect this power. No one will be able to stand against us. No one will ever get in our way again. For now, all you have to worry about is killing them. Take the next step forward, Guren. Claim your power."— Mahiru telling Guren to lose his humanity, Chapter 7, Page 310


 * "W-We have to be quick… If the demon’s regenerative ability is still inside you, the arm might reattach… No, no, why isn’t it attaching yet? At least the nerves…please… What were you thinking?!"— Mahiru freaking out about Guren's wound after he chopped off his arm, Chapter 7, Page 313


 * "You’re lying! You’re lying! It’s all lies, don’t try to make me feel better…"— Mahiru to Guren, Chapter 7, Page 314


 * "If you want to protect me… If you really want to protect me…then come with me, Guren. Kill your followers, kill your friends, and come with—"— Mahiru to Guren, Chapter 7, Page 314


 * "Heh… You always were dashing, Guren. I wish I was the kind of girl who could be swept off her feet like that. I wish I really could just go with you. I know I’d be so happy if I did."— Mahiru to Guren, Chapter 7, Page 314


 * "Ha! Pretty words. But are words all you’ve got to persuade me? What about strength? Why don’t you just knock the sword out of my hands, grab me in your arms, and make me listen to you? That’s right. Because you can’t yet, can you? I’m so much stronger than you that it’s almost heartbreaking. I guess that’s what makes me the hare. Hurtling headlong toward destruction. I’m still waiting for my tortoise prince, Guren. Try and save me if you like, before it’s too late."— Mahiru to Guren, Chapter 7, Page 315


 * "In the end, you’ll fall. Your heart will grow black and twisted, just like mine. Do you see, Guren? We just can’t stay apart. We’ll keep each other company on the road to hell."— Mahiru to Guren, Chapter 7, Page 316

Book 3

 * "So you’re the one who survived, to plant a seed in me?"— Ten-year-old Mahiru when she meets Shinya, Prologue


 * "I have no interest in you. Please just be yourself."— Mahiru to Shinya, Prologue


 * "My heart already belongs to somebody else. There’s no room left for you. That’s what I came here to tell you today."—Mahiru rejecting Shinya, Prologue


 * "Ahaha. All I ever wanted was to have a normal life… To be a normal girl who can fall in love with anyone she likes."— Mahiru to Shinya, Prologue


 * "Hmm… I’m not sure. But whether Guren is strong or weak, my feelings for him won’t change."— Mahiru o Shinya when he asks if Guren is as strong as she is, Prologue


 * "I’m pretty sure Guren is strong, though… He’s probably much stronger than me."— Mahiru to Shinya, Prologue


 * --Do as you like.— An email from Mahiru to Kureto after he announces Shinoa’s death sentence, Chapter 4


 * "Hmm? I never knew Kureto had such a Lolita complex."— Mahiru to Shinoa after Shinoa reports that Kureto threatened to have her raped, Chapter 4


 * "They won’t? I’m pretty sure that Father places much greater trust in me than he does in you, Kureto. It isn’t hard to believe that a weak person would be jealous of a strong one. Remind me, Kureto, which one of us is stronger? I hate to break it to you, dear sweet brother, but I’ve never once felt jealous of you. Do you see what I’m getting at here?"—Mahiru to Kureto, Chapter 4


 * "I…just wanted to hear your voice…"— Mahriu to Guren on the phone, Chapter 4


 * "W-Wait! Don’t hang up, Guren. If you hang up now, we might never be able to speak again."— Mahiru to Guren on the phone, Chapter 4

Mahiru’s voice suddenly grew strained. Her breathing became ragged. Guren had witnessed this before. Several times, when they had met, it had seemed as if Mahiru were suffering from a split personality. When it had happened before, Mahiru had told Guren to run. Away from the demon. That she was already lost. It could all just be an act. But if it wasn’t…— Mahiru to Guren, Chapter 4
 * "No. It’s not like that. I wanted… I… N-No… Not yet!"


 * "Yes…I had to call now…while the demon part of me was still asleep…"— Mahiru to Guren, Chapter 4


 * "I want… I want you to kill me… I’m in control of myself less and less every day. I’m barely here at all anymore. It has to be now, before it’s too late… While I can still resist—"— Mahiru to Guren, Chapter 4

In fact, Guren had a feeling she might already be crying. He could hear a faint, wet sniffling as she spoke. "It’s already too late…"— Mahiru to Guren, Chapter 4
 * "GUREN!!" screamed Mahiru. She sounded on the verge of tears.


 * "I’m sorry, Guren. I’m so sorry."— Mahiru to Guren, Chapter 4

"…" "I love you, Guren." "…" "Please, let me die while I’m still capable of feeling this…"— Mahiru to Guren, Chapter 4
 * "G-Guren."

Because one day, Mahiru began having dreams. Those dreams were dark. Very dark. In her dreams, a demon spoke to her and queried her from the shadows.— Reading about Mahiru’s childhood, Chapter 4
 * While the researchers may have given up, the project didn’t truly end there..


 * As the years passed, and Mahiru’s body matured… As her heart and her emotions, her vanity, her sexuality, and her need for recognition grew, the demon’s voice, too, grew louder.— Reading about Mahiru’s childhood, Chapter 4

Instead, Mahiru used herself as a guinea pig, engaging in a long and lonely fight.— Reading about Mahiru’s adolescence, Chapter 4
 * Working with the Hiragis had never been an option. Going to them would reveal the presence of the demon in her sister, who would be subject to experiments without delay.


 * "I’m not human anymore, Guren… You can’t hold me. I’ve lost that right. I can’t be with you any—"— Mahiru to Guren, Chapter 4


 * "You…don’t love me, do you? Of course, you don’t. It’s been ten years, after all… I’m not even human anymore… How could…how could anyone love a vile monster like me?"— Mahiru to Guren, Chapter 4


 * "Please, Guren… I want you to take me… Will you sleep with me? Even if I am a monster?"— Mahiru to Guren, Chapter 4


 * "I don’t know… I don’t know anything, anymore. I’m just so… so tired—"— Mahiru to Guren, Chapter 4


 * "Heh..heheh, I didn’t expect you to kiss me like that… My heart’s beating so fast I think it might explode."— Mahiru to Guren, Chapter 4


 * "Yes, I have. I ate Shinoa’s demon. I was so desperate to save her that I swallowed it up whole. But that turned out to be my downfall. Once I had two demons inside me, I couldn’t hold myself together any longer. Still… I might be broken, but I don’t think I’ll forget what we did today. I love you, Guren. And I thank you. You finally gave me what I wanted. Thanks to this…the last bit of weakness left in my heart has finally died. Mahiru, the pathetic little six-year-old girl who called you on the phone to cry about how much she loved you, has let go of her attachment to this world and passed away."— Mahiru to Guren, Chapter 4


 * "I’m sorry for getting you wrapped up in all of this, though, Guren… I managed to get the demon out of Shinoa, but in the end I wound up splitting it with you. Now, you’re going to become a demon, too. I guess I still wanted to depend on you a little…"— Mahiru to Guren, Chapter 4

"God is angry. At us, for our greed. At mankind’s vile nature and insatiable desire. At the unspeakable research we’ve been pursuing. "The land will rot. "Monsters will roam the Earth. "Poison will rain from the sky. "The Seraph of the End will blow its trumpet, and this world will fall. "Mankind won’t be able to survive in the new world. Not the weak, at least."— Mahiru explaining how the world will end to Guren, Chapter 4
 * "I already told you, the world is going to come to an end. It’s exactly what it sounds like. The adults will be destroyed first, because they’re the most tainted and filled with desire. When it happens, everyone in the world over the age of thirteen will die…


 * "Come, Asuramaru…"— Mahiru summoning Asuramaru, Chapter 4


 * "Behind killing everyone from the Thousand Nights? I concocted a rumor that the Hiragis did that. Today, the Thousand Nights are going to get their revenge. And then the Hiragis will get revenge against the Thousand Nights. And then the Thousand Nights will—"— Mahiru to Guren, Chapter 4


 * "It looks like it’s started. Until yesterday, I was the only hare in the race… but things are going to change today. Everyone will need to become a hare. Everyone in the world. Make haste, make haste."— Mahiru to Guren, Chapter 4


 * "I’m trying to be with you, Guren. To live with you, even if it’s in the next world. Even if it’s in a world where mankind can no longer survive. But for that to happen, we’re going to have to be demons."— Mahiru to Guren, Chapter 4


 * "Haha. Look at how vile humans are. Give them the slightest reason to doubt, and they tear each other’s throats out. Is that the side you want me to join?"— Mahiru to Guren, Chapter 4


 * "There’s one thing I know, though, Guren. You’re strong. Very strong. That’s why I love you. Kureto can’t hold a candle to you. If you ever get serious, the whole world will tremble at your feet. Because human strength lies in naïveté, weakness, and vileness. A demon’s favorite things."— Mahiru to Guren, Chapter 4

Book 4

 * "You don’t have much time, Guren… If you don’t hurry, you’re going to be too late. Mito Jujo is waiting for you in the audiovisual room. She’s on the brink of death, and she’s hungry for you. She needs it so much. You should take her, Guren. Just like earlier, when you took me."— To Guren, Chapter 2


 * "It’s okay. It’s only natural for humans to feel lust. But you’ll never be able to get what you want. Not in this world. You just aren’t strong enough. I’m the one that Guren loves. Not you. He’ll never love you."— Mahiru to Sayuri, Chapter 2


 * "Ahaha. I love how you try to protect these humans, Guren. I love how greedy you are. How you try to have it all, and in the end wind up with nothing. I love you so much, I want you to have even more of the demonic poison!"— Mahiru to Guren, Chapter 2


 * "That doesn’t matter. What’s important now is that my brother, Kureto, is about to bring the cursed gear project to nearly 90 percent completion. He’s going to create an antidote to save you. People will be able to use it to wield cursed gear while still holding onto their sanity… But greatness requires more. Any plan put together by a rational person like my brother will always include a large margin of safety. An approach like that will never aim high enough."— Mahiru to Guren, Chapter 4


 * "Hang up on me now and I’ll make sure you regret it for the rest of your life."— Mahiru to Guren, Chapter 4


 * "Oh, Guren. You can’t just screw a girl and run."— Mahiru to Guren, Chapter 4


 * "Kill me, so I can live on inside of you forever."— Mahiru to Guren, Epilogue


 * "This makes me love you even more…but I’m afraid a lovers’ suicide is out of the question. I’m entrusting the future to you. When everything is in hopeless ruins, I want you to be the last ray of light shining on the world."— To Guren, Epilogue

Book 5

 * "You look human to me."— Mahiru to Yuichiro Amane when he says his parents called him a demon, Prologue


 * "But if you are a demon, or a monster, or whatever, does that really mean you shouldn’t get to live?"— Mahiru to Yuichiro, Prologue


 * "I am… I have my own battle to fight, so you’ll have to stay strong on your own. You do that, and someday I’ll come back to let you out of there."— Mahiru to Yuichiro, Prologue


 * "I don’t think any human living is worth anything. No one is really important. Everyone is just a cog in the end. Get rid of this or that cog, and the next one will be born soon enough to take its place. But tell me, Yu, if there’s no real meaning or value to life, what will you live for?"— Mahiru to Yuichiro, Prologue


 * "Ahh, you’re so adorable, Guren. Even in the situation you’re in, you still don’t know what to do. You want to be kind to everyone. You’re exactly the type of person who’s bound to turn to your demon for help. And you’ll fall so much deeper, so much darker than I did. You pretend that you’re good and just, but someday, when hope is gone and the future is lost… Ahh, I can’t wait, Guren. I can’t wait to see that happen. But I think we’ve talked enough for now."— Mahiru to Guren, Chapter 1


 * "Kureto, how about you let your adorable half-sister give you a little advice. If you plan to keep using that demon sword, you should know that always doing things the correct way will only make you weak… As long as you stick to taking baby steps, you’ll never be able to stop me in time. Justice? Reason? Cast off those chains, Kureto. If you don’t, you’ll never catch up to me."— Mahiru to Kureto, Chapter 1


 * I don’t know what it’s like to be loved by your parents, so I don’t understand that feeling.— Mahiru reflecting to what a child said about thanking her parents back when she was little, Chapter 2


 * "Junji, you don’t need to be scared. We’re actually just an ordinary, happy family. You’ll like it with us."— Mahiru to Junji at the Hyakuya Orphanage, Chapter 2

That she had the right to be happy. But no such right existed. If you wanted happiness, you had to scratch it out yourself, tearing and screaming, from the jaws of death.— Chapter 2
 * Mahiru had thought the same way when she was little.


 * "You think so? Maybe I’m just patient. My dream, actually, is to be a nice, traditional housewife. Long-suffering, you know?"— Mahiru to Krul Tepes, Chapter 5


 * "Ahaha. The turtle has begun to run. I’m going to have to make sure he doesn’t catch up to me," Mahiru muttered to herself. But deep down, what she really wanted, really desired, was for that turtle to overtake her and put his arms around her.— Mahiru to herself after Guren moves outside her predictions, Chapter 5

"Tock. Tock. "The sound of desire. "The footsteps of destruction. "Someone cries out. Man’s sins are too great. "Someone cries out. Man’s pride has grown too large. "Like Icarus. "Like Babel. "The second hand continues to race. "Avarice marches onward. "Toward the end of the world. "Toward a world of blood. "This is the story of how man goes extinct once more."— Mahiru to Krul, Chapter 5
 * "Ahh, I can hear it again, that noise," Mahiru said in a singsong voice, as Krul stared on.

Book 6

 * "Because they killed my mother… The Hiragi Clan hunted her down and killed her. My father barely ever even looks at me. So I decided to do the one thing I knew would bother the Hiragis the most."— Mahiru to Guren about why she first approached him, Prologue


 * "I wonder how these bands are created… I’ll have to look into it and make my own."— Mahiru to herself after tearing her UV-suppressing armband to pieces, Chapter 4


 * "Ahh, I must be thirsty for blood."— Mahiru to herself while thinking of Guren, Chapter 4


 * "Not that I really qualified as human even before becoming a vampire."— Mahiru to herself, Chapter 4


 * "Are you that scared of me?"— Mahiru to Guren, Chapter 4


 * "I came to protect what’s dear to me… You… and my sister."— Mahiru to Guren, Chapter 4


 * "Did you just peek up my skirt, Guren? You had that kick coming, you naughty perv!"— Mahiru to Guren, Chapter 4


 * "I’m still in the lead, Guren. But you’ve gotten very close. Hurry now, catch up to me and take me in your arms."— Mahiru to Guren, Chapter 4


 * "Before we go any further, I need to tell you why I’m here. I’ve placed the cursed gear I dropped earlier, Shikama Doji, in your pocket. Give it to Shinoa. As long as she has it, she should be able to survive after the world ends…"— Mahiru to Guren, Chapter 4


 * "Ahh… I love the way you smell, Guren. I wish we could stay like this forever."— Mahiru to Guren while wrestling with him, Chapter 4


 * "Ahhh, I can’t hold back any longer. Just a little, Guren, just a little taste."— Mahiru to Guren before biting him, Chapter 4


 * "You see? You haven’t caught up yet, after all."— Mahiru to Guren, Chapter 4


 * "Are you calling to invite me on a Christmas date?"— Mahiru to Guren, Chapter 4

Seraph of the End: Vampire Reign

 * "Silence, Demon"— Her order to Noya after swinging a sword at his mouth for encouraging Guren to spill sensitive information, Chapter 83, Page 31
 * "Hang in there. I'm going to rescue you... ...Shinoa"— Fighting the first and meaning to free Shinoa from his possession, Chapter 85, Page 23
 * "Saito! You're betraying us?!"— Surprised at Saitō attacking Guren and meaning to consume their power, Chapter 84, Page 25
 * "Ooh, you're fast. But you're Krul's vampire, so no wonder I guess."— Commenting on Mika's speed and aware of his connection to Krul, Chapter 85, Page 26
 * "What, me? I'm everybody's favorite lovely idol, Mahiru!"— Happily introducing herself to Mika, Chapter 85, Page 27
 * "Oh right, right. Now isn't the time. I have to hurry and overwhelm you while the life-absorption barrier is still up..."— Remembering her time limited plans before engaging Mika in combat, Chapter 85, Page 27
 * "Aww Don't you remember me? From the prison? You were five. They called you demon spawn. Your own parents even tried to kill you. A poor little monster, all lost and alone, with no reason left to live. Well, little monster? Did you find a new reason?"— Both remembering Yu and recalling their conversation about his circumstances, Chapter 86, Run From Your Friends, Page 23


 * "Ooh! Ooh! You want me inside you? Ohmigosh, Guren. You are sooo lewd."— Her reaction to being told to get back inside Guren, Chapter 87, Cannibal Family, Page 8

Trivia

 * Mahiru 「真昼」 means "Midday."
 * Hīragi 「柊」 means "Holly."
 * Mahiru is the only character known so far to be a demon who is possessed by another demon. It is almost as if the demon itself replaced Mahiru completely, besides her appearance.
 * Both Mahiru's demons, Asuramaru, and Shikama Dōji are currently in possession by a male and female lead of the manga series.
 * According to the light novel, she and her sister Shinoa were born with demons inside of them.
 * In the popularity poll, Mahiru earned 8th place at 957 points.
 * If she were alive, she would be 24 years old.
 * Her desire before her death was to become an ordinary girl, to love a favorite person, to give birth to a child.