Mitsuba Sangū

Mitsuba Sangū (三宮 三葉) is one of the main female deuteragonists of the Seraph of the End: Vampire Reign manga series. She is the younger sister to Aoi Sangū who was a special duty second lieutenant of the Japanese Imperial Demon Army. Mitsuba also appears in other Seraph of the End media. Having lost her previous squad in a Horsemen of the Apocalypse attack, Mitsuba is aware of the harsh realities of the world, and while realistic, is ready to fight back against the rising vampire threat.

In combat she wields a Cursed Gear battle axe, Tenjiryū. Affronted at being assigned to Shinoa Hīragi's squad in the Moon Demon Company, where she became the fifth member, Mitsuba also has no patience for Yūichirō Hyakuya for his attitude. Willing to sacrifice herself so others can live, Mitsuba would help defend Shinjuku from a vampire invasion, yet feel a promotion from the ruling Hīragi Family was given just because of her prestigious family name. Remaining brave and capable, Mitsuba helped in the campaign targeting vampire nobles in Nagoya.

Losing her position in the Demon Army when she defects along with the rest of Shinoa squad due to Kureto Hīragi and Guren Ichinose sacrificing their own troops, Mitsuba remained loyal to her team, where they had to work together with enemies as the threat of Shikama Dōji arose. Remaining close to Shinoa, she also works well with Yoichi Saotome and Shihō Kimizuki of the squad. Conflicted at who they could trust, Mitsuba would follow the rest of her team in helping to enact Guren's plan to resurrect humanity.

Appearance
She has long blonde hair tied up in pigtails and large purple eyes. Mitsuba is noted to have a curvaceous figure, in particular, Shinoa has made several observations about the size of her chest.

Mitsuba wears the standard Japanese Imperial Demon Army uniform which consists of a long-sleeved black coat, with a standing collar. This has a red bow tie around it, and she has her sleeves rolled up. The coat has two rows of gold buttons on the front, light green details including the shoulder epaulettes which has a Sam Browne belt passing diagonally over her right shoulder. Rather than the standard white gloves, Mitsuba wears black gloves and a white web belt with a gold waist-plate. She also wears the standard black skirt (with black shorts underneath) along with knee-high black boots. She sometimes wears the black cape part of the uniform.

Personality
Shown to be a serious and by-the-book soldier, Mitsuba outright dislikes those who break the squad battle formation and commit to individual actions. This is heavily influenced by an event in her past; in her previous squad, Mitsuba was headstrong and acted out of bravery in charging at an enemy. In addition to having a desire to rescue a comrade, while seeming noble, once her movements broke the formation of her team it lead to her squad's annihilation. Feeling responsible, Mitsuba would focus on valuing staying in formation and following the rules, which she enforces on the rookie soldiers below her. She is prepared to try and kick Yu when he fails to take the formation seriously and expressed a similar charge in and fight attitude. In response to sudden threats appearing or being ambushed, Mitsuba remains level-headed and focuses on the team.

Acting as a unit that is unimpeded by fear, Mitsuba did not want Yu to save her when she was caught by the vampires after she was caught in an ambush. Thinking that he would die if he tried, Mitsuba ordered them to leave her and save themselves. Not concerned for her own wellbeing, Mitsuba was only upset at the idea that the loss of her squad could repeat itself as she watched others fight to save her. However, with her life saved by him, Mitsuba learns to have more faith her in comrades instead of restraining their actions with her concern. Nevertheless, even when knocked off her feet by Crowley in quite a savage attack, Mitsuba was undaunted. In gripping the vampire noble's leg to impede his movements, Mitsuba again focused on having her squad escape, never mind what would happen to her.

Shown to be confident of her skills, Mitsuba boasted to her squad that she had joined the Moon Demon Company at the age of 13. Mitsuba is shown to be annoyed when Guren puts her in Shinoa's squad, of the view that she is not fit to lead. When the notion is dismissed by Guren, it is much to her chagrin. Upon locating her squad leader, she reacted by generating her cursed gear to clash with Shinoa's scythe. With time, Mitsuba is shown to ease into her role of second-in-command. Accepting Shinoa as her squad leader, Mitsuba is happy to pick up on her cue that maybe she was chosen by Guren to whip the newcomers into shape, which she does by organzing them.

In various settings, Mitsuba can become enraged and will speak her mind. Aware of a vampire ambush when she saw one, Mitsuba revealed the problem at once. In sharing her frustrations concerning Yu, she also cut the conversation short to order Shinoa to not come into her shower area. Coming across Yu touching Shinoa's neck and making an assumption, getting jealous easily as well, Mitsuba was then told to use her indoor voice by Kimizuki. Despite this, Mitsuba can adjust her temperament when necessary. Speaking nicely to a young girl was one such case, Mitsuba is also confident and happily shares her knowledge on demon possession with her squad. Working well with Shinoa, she often provides details. Concerned at Yu's meeting with the Hiragi family, Mitsuba voiced her unease that she is incompetent, feeling she done nothing on the battlefield but was still promoted. Talking about what is bothering her makes her feel better.

Enjoying a practical joke, Mitsuba will quickly pick up on what Shinoa is instigating and join in. At learning that a young girl had betrayed them by providing false information, Mitsuba was not angry at her, rather the vampires who put the girl in that position where her families' safety was placed at risk. Also learning of Yu's background, she spoke how he done the right thing to leave the others behind and live. Her quick reactions and adapting to situations is also helpful in combat, where Mitsuba is ready to deploy her Tenjiryū manifestations to assault targets or provide cover to her comrades. Sensibly she did not compromise her status in a Hiragi family meeting, neither gave away too much information on what happened at a battlefield. Acting casually and being sensible was effective in attempting to sway suspicious minds that Yu was uninvolved with what they were investigating.

Mitsuba is proud of her family, yet she hates the fact that she is given special treatment and advantages just because of her family name. Since she is a Sangū, Mitsuba feels that she has to uphold her family's reputation all the time, and despite being second-in-command in Shinoa's squad, feels as if all of her teammate's lives are her responsibility. Unlike other ruling families, Mitsuba does not see her comrades as disposal, rather she greatly cares for them. Spoken to curtly, Mitsuba reminded the speaker she was a member of the Sangu family. Having an inferiority complex towards her older sister, Aoi Sangū, she feels under-accomplished when compared to her. Mitsuba was prepared to put her squad first over her family name.

History
When Mitsuba was thirteen she joined the vampire annihilation force. At some point she was assigned to a five member squad. In 2017, when her comrade Shirō was in danger, Mitsuba broke formation to save him from a Horseman of the Apocalypse. When she slashed its arm to save Shirō, the monster used its other arm to strike her, but Mitsuba's squad leader saved her by using himself as a human shield, which caused his death. Memories of the loss of her squad where she felt responsible would trouble her to the present day, and greatly shape Mitsuba's conduct.

Shinjuku Arc
Mitsuba Sangū is yelling at Guren Ichinose for putting her on a squad of rookies and, better yet, assigning her to work under Shinoa Hīragi. Stood outside the walls of Shibuya, at locating her, Mitsuba draws her Cursed Gear axe, Tenjiryū and clashes with Shinoa draw their weapons. With this forcibly brought to an end by Guren and scolded, Mitsuba then makes it clear she hates short-sighted people who break formation when she attacks Yūichirō Hyakuya right away for saying he will charge after a vampire no matter what. With it decided, Mitsuba becomes the fifth and final member to Shinoa squad, with Yoichi Saotome and Shihō Kimizuki being her new comrades as well.

The newly formed squad are given their first mission by Guren: Free the humans being held by vampires in Harajuku. Afterwards, they are to then meet up with the main army in Shinjuku. Walking through the devastated cityscape to Harajuku, Mitsuba lectures the squad about the Horsemen of the Apocalypse that target humans. She also details the importance of maintaining formation after overhearing Yu tell Yoichi that he sometimes went outside Shibuya as a response to the latter's question about being outside the city walls.

Suddenly aware of a human girl being chased by a Horseman, Mitsuba takes charge and orders the squad to stay back. Along with Shinoa, they explain that the girl is obviously bait. Mitsuba regrets not being able to do anything, but says she understands this is for the best. When Yu disobeys and presses forward anyway, and the vampires attack on cue as they spring their trap, Mitsuba is ready to defend him. While the girl was saved, Mitsuba slaps Yu afterward for his insubordination. In a discussion concerning her, Shinoa advises Yu to not take it personally because Mitsuba also has a painful past.

Showering with Shinoa, her temper is cooled where Mitsuba is told that acting against orders was not the cause of her squad's demise. Despite that, Mitsuba orders Shinoa to stay in her own shower, only to be pounced upon where they are both naked.

Having new information on their target, Shinoa squad enter the Omotesando Station to exterminate the vampires within. As they begin, Mitsuba scolds Yu, being having it pointed out that he even waited for orders this time in slaying a vampire they found. Protected by Yu from another vampire, Mitsuba is surprised at his strength. As she orders the squad to form up, they are ambushed by a group of vampires. Unlike what the child they saved told them, there were actually nine vampires total instead of only seven. Seized by a vampire, Mitsuba does not hesitate to order her squad to escape and leave her behind. While her orders are disobeyed again, Mitsuba's life is saved by Yu. Gathering themselves, Mitsuba and the squad exterminate the vampires.

After hearing Yu tell the child's father some details about his past, in which he left his friend behind when the two tried to escape a vampire city, Mitsuba approaches to ask him if that story is true. Told to not pry or dig into his past, Mitsuba attempts to tell Yu thank you, but she becomes too embarrassed.

As the squad is driving down to Shinjuku, they find it under heavy attack before encountering Thirteenth Progenitor Crowley Eusford. Everyone vacates the jeep when Kimizuki accelerates the vehicle into vampire noble. Mitsuba helps the squad fight Crowley until two additional vampires, Seventeenth Progenitors Chess Belle and Horn Skuld show up. Already outmatched, Mitsuba observes as the newcomers inform Crowley that he is needed by Ferid Bathory elsewhere. After they depart, the squad reaches the gates of Shibuya.

Within the city, they are called to aid forces against a vampire invasion concentrated on the west wall of the city. After the threat is taken care of, Shinoa squad then receive a special PA that orders them to be at the 5th Street Intersection. On the way, Mitsuba is handed Cursed Gear Stimulants to help with her weapon capabilities. Reaching the 5th Street intersection, they face off against more vampires, and Mitsuba sees that one of them is Mikaela Hyakuya, who is Yu's family]], whom was left behind in the vampire city to die.

With Crowley along with Chess and Horn's arrival, the vampire forces on the other side of the battlefield are overwhelming and Mitsuba is ordered to retreat, as with everyone else. Pursued, and easily defeated, Mitsuba is caught and bitten by Chess Belle where her blood is drained. Mitsuba, with other members of the Moon Demon Company, and Shinjuku itself, are saved with the arrival of the Japanese Imperial Demon Army forces led by Shinya Hīragi and Kureto Hīragi.

Post-Shinjuku Arc
After Yu wakes up from a week long coma after transforming into a on-winged monstrous being, Mitsuba is the third to barge into his room. Coming across the scene of Yu touching Shinoa's neck, with the latter blushing profusely, Mitsuba sees what she sees, before learning that he was just looking at her bite mark. When Kimizuki enters next, Mitsuba is told to be quiet since they are in a hospital.

Having received a promotion to Special Duty Second Lieutenant, Mitsuba is upset what an insult that is to Yu upon meeting him. Feeling that she is weak, Mitsuba then hears that Yu is not laughing at her as she is consoled. Hearing from Yu that she can use that promotion to help him reclaim Mika, she warns him that is a topic that would be raised. Also warning that the Hīragi Family are scary people, Mitsuba sees Yu head into his meeting.

Outside, Mitsuba meets with Shinoa, to be called a useless lump. Responding that does not make her mad because Shinoa is the only one who ever had the guts to say that to her face. They chat about the Hīragi family and Yu going berserk on Shinuku's battlefield. Mitsuba then sees the three boys exit the building, beaten and bleeding with the exception of Yu, who yells at Guren to teach him how to use his Cursed Gear properly.

In order to proceed with Cursed Gear training, Mitsuba, with Yoichi, and Kimizuki arrive to the meeting location half an hour early, yet find Guren, along with Shinoa, and Yu already there. Alongside Shinoa, she begins teaching the boys someplace within a ruined city. Mitsuba manifests Tenjiryū's decoys in a brief spar with Yu to demonstrate manifestation type demons. With assistance from Shinoa, they explain how this works. As Yu wants to begin his training first, Mitsuba monitors him as he interacts with his demon.

While waiting on him, the two girls tease Kimizuki for being so kind when he placed his jacket on Yu, and act as them like they were a loving couple. They end their skit with "to be continued." With Yu's training successful, Kimizuki goes after that with Mitsuba monitoring his condition once more. After that is complete, while the two boys spar, Mitsuba speaks with Shinoa having realized that these three boys may be Guren's handpicked secret soldiers. They consider that the power struggle between the higher-ups may begin soon.

Nagoya Arc
By morning, a meeting has been arranged at Shinoa's room in the barracks. Already there, Mitsuba "helps" Shinoa cook breakfast. By adding sake to an omelet, Mitsuba accidentally starts a fire, yet is saved with Kimizuki's arrival. Speaking that she learned from a book that adding sake to food and lighting it is supposed to make food better, Mitsuba finds Kimizuki take over the cooking. With the squad meeting underway, Mitsuba then listens to Shinoa reveal to Yu that he transformed in Shinjuku. The struggle between Guren and the Hīragis for control of the Demon Army is also a topic. All things considered, Mitsuba with the rest of the squad decide to remain loyal to Guren and look out for one another.

While driving to Nagoya, the squad come across a few Horsemen on the road. After Yu leaps out to slay them, Mitsuba teams up with Shinoa to trick Kimizuki into swerving so as to leave Yu behind. Picking him up ten minutes later, Mitsuba lectures Yu on leaving his team behind before revealing that they ditched him as a prank. Their shenanigans make them late to a gathering at the Ebina rest stop, and Mitsuba witnesses Yu receive the punishment for it.

Entering the rest stop after hearing Yu yell, the squad find Norito Goshi's illusion of him fade, and learn that this is in fact a test for Shinoa. The five of them are challenged to fight a team of three, which involves Guren, with Mito Jūjō, and Shinya as well. Gaining some distance, Mitsuba and Shinoa briefly explain their abilities and form a plan. Out of time, Mitsuba summons decoy demons in an attempt to split up Mito and Guren. While Mito punches through them, Guren gets past Yu and stuns her, where they lose the match, badly.

As they prepare for their furtive mission targeting vampire nobles spread around Nagoya, Mitsuba meets Makoto Narumi and his squad. Mitsuba teams up with Kimizuki to scold Yu and make him behave and be polite. They attack Fifteenth Progenitor Lucal Wesker as two squads combined, with Shinya assisting as well. Mitsuba distracts Lucal from Yu with decoys created by her cursed gear, but they are destroyed with just a swipe of his noble hand. She also helps Shinoa distract him when he charges in to kill Kimizuki. Collectively, they end the combat with Yu cutting Lucal in half, with Narumi finishes him off with Genbushin.

Successful, the Moon Demon Company are to regroup, and Mitsuba sees Sergeant Aiko Aihara arrive with only seven survivors from her squads. Where a large scale mission has failed, with hostages having been taken, Mitsuba and her squad are to join Guren Squad with Narumi Squad to hunt three nobles, which are Crowley Eusford, with Chess Belle, and Horn Skuld.

Reaching Nagoya City Hall, after Crowley catches Yoichi's Gekkouin manifestation, Mitsuba stands by as Guren and his squad discuss what to do. After careful planning, Guren decides that his squad will take his squad to attack Crowley while Shinoa and Narumi Squads free the hostages. They have five minutes to rescue as many hostages as they can. It is also revealed that they are to act as a proper diversion for the main army force that is travelling from Shinjuku. Having a time limit of five minutes, as soon as that is up everyone has orders to retreat to the Nagoya Airport immediately.

In the middle of the rescue operation, after Yoichi reports on the situation with Guren's squad and Yu insists on rescuing him, Shinoa agrees with him but says they only have five minutes. Mitsuba joins the effort where they have specific instructions regarding their plan. Once Yu breaks upwards to attack Crowley from the floor below, Mitsuba helps him and Kimizuki in the fight by producing Tenjiryū's decoys as a distraction. With Chess and Horn also present, the shield Mitsuba forms with Tenjiryū is ripped apart and they are greatly outmatched.

Having to fall back with help from Guren's squad, they are able to rescue Shinya yet have to leave Guren behind. Having escaped, but hearing that Yu intends to head back, Mitsuba is shocked at his plan. When Kimizuki captures Yu after he fights Crowley, she sees him returned in Kiseki-o's Devil's Coffin. Running toward Shinya, they are ordered to move as vampire reinforcements are coming. They join with Narumi Squad and many injured soldiers and flee in the direction of the airport. When Rika Inoue reports seeing a single vampire straight ahead, the orders from Shinya that Mitsuba is to follow is to handle the one noble and keep pushing forward.

With the vampire turning out to be Mika, who engages the Moon Demon Company, the squad register who he is. Although he is defending himself and avoiding combat, he is still heading to their location, and where Mitsuba tries to block him, her axe is knocked away. When Shinya uses the distraction to stab Mika through his back and chest, Mitsuba is alarmed. After Shinya is blasted aside by Shinoa using Shikama Dōji's manifestation, Mitsuba is with her squad in defending Mika from the Moon Demon Company members who want him dead, before helping him to escape with Yu. Shortly after Mika flees with Yu, vampires rain down around the Moon Demon Company, and although Mitsuba reaches the airport there is nothing waiting for them. Raising that while the attacks against them have stopped, Mitsuba adds that the vampires are most likely still pursuing them.

A van pulls up at Nagoya Airport, and Mitsuba sees her elder sister, Aoi Sangū step out. Although noticed by her, Mitsuba finds she quickly turns away. There is alarm when Kureto is seen to have arrived. After Kureto orders Aoi to kill the "sacrifices", Shinoa orders her squad to quickly prepare to retreat. As Aoi launches chains from the ground, a pair of the sharp tipped weapons strike down at Narumi from above, but Mitsuba and Kimizuki block the attack. In response to Kureto murdering the survivors, Mitsuba with Shinoa order a retreat before being surprised at Yu and Mika's arrival.

Found by an army of vampires under the command of third progenitor Krul Tepes, as those forces clash with the Japanese Imperial Demon Army's, Mitsuba and the team now including Mika and Narumi are helped to escape by Shinya and Guren squad. Fighting their way through the enemies, they make heir escape.

The experiment continues, where Mirai Kimizuki is heavily involved, and revealed to be controlled by a seraph, namely the Fifth Trumpet. Also finding that the demon Abaddon has been successfully manifested, Mitsuba sees Yu awaken as a seraph who deals with the monster. As the squad makes their escape from Nagoya Airport, Shinoa tells her squad that they are now seceding from the Japanese Imperial Demon Army.

Three months later, the group is near the sea.

Post-Nagoya Arc
Yu has been transforming into a demon for increasing lengths of time, and Mitsuba with Shinoa, and Kimizuki, listen to his and Mika's exchange from outside the cabin they are in. Learning that Horsemen are attacking the village, with the exception of Narumi, the group repel the dangers where they are thanked by the villagers. Food that Makoto has located is brought back, and Mitsuba with the squad notice that Mika drank their blood they collectively contributed into a bottle and approach him. After Yoichi asks if their blood was okay, where Mika replies it was gross, Shinoa rambles about the pure and sweet blood of a virgin before urgently wondering if unchaste blood got in there while Mitsuba is looked at.

Bring up their future plans, Mitsuba summarizes what has been going on. She says that the Japanese Imperial Demon Army will probably hunt them down and kill them, so their presence puts the villagers at risk. They mention they cannot travel overseas because of how acidic and poisonous the blood-red oceans are, then monsters even worse than Horsemen swim in their depths.

The group suggest surrendering, yet Mika rejects the idea of returning Yu to the army to prevent him from becoming a demon. Hearing Makoto affirm that he will save Yu no matter what in order to give his friends' deaths meaning, and Kimizuki state he will do absolutely anything to save his sister, even betray the rest of them, Mitsuba hears out the suggestions. Yu suggests meeting up with Guren, but Shinoa vetoes that idea and says they cannot trust him. Makoto tells Mika this is the circle of discussion they are stuck in and asks if he has anything to offer.

With Mika sharing that the vampire queen, his sponsor, participated in the Seraph of the End experiments, they may be able to trust her. While she was captured, rescuing her might be their least complicated option. Mitsuba agrees to the plan, and it is addressed how the Demon Army is the most dangerous organization in Japan. Accordingly, the squad decide their next objective is to rescue Krul Tepes before Yu becomes a full demon. Learning that Crowley and Ferid are nearing them by car, the group move to escape. After Crowley lands in front of their group, Mitsuba is targeted and struck with such force that she is knocked off her feet and sent flying. Shocked to realize she is okay, Mitsuba is then thrown to the ground. She latches onto Crowley’s leg and orders the squad to abandon her and flee since they cannot waste time here.

When Kimizuki manifests Kiseki-o's Devil Coffin power and begins his count of nine, with Crowley considering pulling back, Mitsuba is asked if she would release his leg. Refusing, and threatened with having her arms cut off, Mitsuba ignores that and declares she will no longer be the weak link. Unable to defeat him, after Yu surrenders, Mitsuba witnesses Ferid arrive and present Akane Hyakuya's head in a jar to him.

Having little option but to go where Ferid and Crowley want to go, Shinoa Squad boards bus and Mitsuba wonders if they really should have. Hearing Shinoa say there was no other way and Ferid has Akane as a hostage, it is also mentioned by Mika that Ferid is controlling them and they should not be involved with him. On the bus journey, Mitsuba learns that Ferid has Narumi's squad in his mansion, and that Guren caused the apocalypse by reviving his squad and Shinya where he has been burdened by the price humanity has paid.

Within a lavatory during a bathroom break, Mitsuba is made fun of by Shinoa for taking forever. Mitsuba claims she was looking for an exit, then asks if Shinoa believes in Ferid's story about Guren. Joining the others in the men's bathroom, they wonder how long they should trust Ferid. While they decide to betray him before he betrays them, the squad eventually reach their destination. Exiting the bus they find that it is Osaka Bay, which is uccupied by many vampires who have arrived in Japan from abroad.

Osaka Arc
Watching as Third Progenitor Lest Karr pulls Ferid's heart from his chest, Mitsuba backs away as Ferid nearly kills Kimizuki by drinking his blood and wonders if anyone else wants to provide some. She can only wait as Second Progenitor Urd Geales asks who the humans are, where Ferid replies they are his favorite humans. Mitsuba gets back on the bus with the rest of the squad, and watches an anemic Kimizuki request meat. She gets mad at Yu for thinking about leaving as it would draw the vampires' attention to them.

After Urd and Lest Karr sentence Krul and Ferid to sunlight exposure torture, the squad go with Yu's decision to rescue the tortured vampires as their information is needed. Mitsuba and the squad are driven by Crowley to Ferid's Mansion. The group marvels at how large Ferid's mansion is, before Tenth Progenitor Fuola Honte appears. Although he attacks, Fuola is soon killed Crowley. While Shinoa is glad that they have an ally who is strong, Mitsuba questions if he truly is their ally.

On the extent of their strength, the squad are challenged by Crowley to see if their formation can beat him but they are quickly defeated. They hear Crowley say they must be able to get stronger quickly to rescue Ferid because the one in their way is a fifth progenitor.

Shibuya Arc
Along with the rest of the squad, Mitsuba can only watch as Shinoa is undergoing the transformation into a vampire.

Stood near to Narumi and Yu, with Yoichi and Kimizuki nearby concerned, Mitsuba states it sounds like a battle. Alarmed at the electrical needle scientists are guiding towards Yu’s neck she asks one to hold on, if he is sure he should be sticking Yu with that thing. Mitsuba erupts with indignation at being called a brat, demanding to know what kind of attitude is that. Proclaiming herself a member of the Sangū family, he should have some respect. Pausing as Yu tells her he will be fine, and to go be there for Shinoa, she shouts for him as he is struck with the needle.

Asking the scientist if he is sure this is right, Mitsuba is perplexed, caught off guard at having a spell tag suddenly attached to her forehead. Avoiding the detonation, she asks what the heck he did that for. Evading an additional fusillade of them, Mitsuba is still in shock and questions what is he doing, who is he. Witnessing the man reveal himself as a member of the Hyakuya Sect, Mitsuba then reacts by conjuring Tenjiryū, having no intention of allowing him to fulfil his mission. After he slices a portal through reality using Jigenso, she see's the Hyakuya Sect agent escape with Yu who is unconscious. Ordering him to wait, Mitsuba is unable to stop him before calling to everyone that they have trouble, somebody just took Yu and disappeared.

Literally running into Shinoa who has just been freed from Shikama Dōji's possession, Mitsuba shares her concerns of Yu being kidnapped by the Hyakuya Sect, Shinoa being taken away and going nuts, and then herself separated from everyone. Her sniffling ends when she realizes Shinoa might be making fun of her, then comments on her chest size before being relieved that Shinoa is herself again. Resolving to rescue Yu, she asks Shinoa how they will go about this.

Noticing Yoichi running nearby, Mitsuba joins with him and Kimizuki who is unconscious, along with his sister who has been killed by Guren. Startled, Mitsuba also hears how Yoichi's sister can be revived, as well as Mirai.

In the jeep that Kimizuki is driving, Mitsuba shouts to Shinoa that Yu is over in the direction of the crumbling buildings. With her axe ready, she fully supports heading to rescue Yu who has been spotted.

Grasping Kimizuki's head, Mitsuba orders him to floor it since Yu is in trouble, before turning to check Yoichi. Asking Shinoa if she is okay, Mitsuba seizes her foot as she is pulled out of the vehicle by her cursed gear. Mitsuba is returned to the truck thanks to Yoichi and then Kimizuki's efforts. She does not agree with Shinoa's view that the power of the first vampire is amazing and continues to be transported to where Yu and Mika are.

Post-Shibuya Arc
Drawing closer Mitsuba joins the others in waving when Yu notices them. After escaping Demon Army territory, Mitsuba is with Shinoa within an apartment block room checking a fridge. After seeing the can, Mitsuba is thrilled to announce to Yoichi that they have found lots of cans of soda. Rather than focus on what Yu and Kimizuki were saying, Mitsuba agrees finding drinks is more important since they have not had much rain lately and so potable liquids are important. She discusses how old sports drinks are passable but old canned soda can start tasting like the can, before she tosses a can to Yoichi and encourages him to drink up.

As Yu and Kimizuki spar outside, where Shinoa explains that is how boys see who is stronger, Mitsuba states it is dumb and girls decide who is better through bust size. She does not understand why Shinoa and herself need to talk when Shinoa does not have a bust line to speak of, before being pounced on by her. Mitsuba is dizzy from the effects of her soda which turns out to be alcoholic.

When Krul enters the room, Mitsuba joins Shinoa in attacking this new challenger. She is prevented at capturing "the new boobs" and is held by Krul before the drinks have their effects. Mitsuba lays on the floor, indifferent as Krul interacts with Yu and Kimizuki. While Yoichi said Mitsuba also feels really sick, she is picked up by Yu which causes her to blush.

Standing before Krul and hearing Yu hold Guren accountable for his traits, Mitsuba voices that Yu was in fact born with a horrible attitude. Mitsuba observes as Yu makes an earnest appeal for Krul's help in rescuing Mika. She does not respond to Krul's enquiry of how much of the situation they understand, neither to who their enemies are, who they are rescuing, resisting, and to what purpose. Hearing that Mahiru Hīragi is involved, Mitsuba comments that she is the genius who invented cursed gear and then died. She adds that without cursed gear, humanity might really have gone extinct after the catastrophe. Whilst most people consider Mahiru the saviour of the world, Mitsuba is aware of rumors that she betrayed the Hīragi family, though concludes that if anyone would know the truth it is Shinoa.

Mitsuba is shocked to see Krul reveal Shikama Dōji to in fact be in possession of Shinoa. Once Guren arrives, who is with Mahiru as a spirit, Mitsuba is called upon to put up a barrier outside to turn Mika into cursed gear. Mitsuba appears concerned at Kimizuki as a demon striking at Guren. She is happy to see Shinoa regain consciousness but does note how Yu places his hand on her shoulder. Along with the rest of the squad, Mitsuba is asked to please help Guren with resurrecting everyone, a goal that she is surprised at.

With a spell circle being created on the rooftop, Mitsuba understands Guren's order to handle the standard parts of the circle for subduing a black demon. Underway with it, Mitsuba tells Yu that it is a standard spell circle four and is exasperated at Yu's unfamiliarity with it. Perplexed at Yu holding his head in his hands, Mitsuba is aghast at Yoichi also not recalling the details. Following Kimizuki's directive to take the Eastern quadrant, she sets about drawing the intricate designs of one of the three smaller circles of the construct. Continuing this, Mitsuba then hears that Yu heard Mika calling for him and glances to Yoichi. Beside Kimizuki, she listens to what Yu has to say. Impressed with the spell circle being activated, with Yu heading to save Mika, Mitsuba follows up what Yoichi mentioned about them being family and adds if Yu lets himself get possessed then she will send him flying.

Mitsuba joins hands with others before Yu departs. She is stood near Yoichi and Kimizuki with Yu unconscious on the spell circle. When Kimizuki and Yoichi discuss how Yu is not waking up, and the former demonstrates Yu's Octopus Face, Mitsuba joins in laughing. It is recollected that before Yu entered the spell circle he was asked by Guren if he remembered how to subdue a demon, where Mitsuba did not find Yu's assertion that he could do this to be reassuring. She was quite startled to hear that Yu did not attack his demon Asuramaru at all to make his contract. Along with Kimizuki and Yoichi she answered affirmatively when asked if weakening a demon to subdue one is what they done.

Standing near Yu who remains unconscious on the spell circle, Mitsuba is startled to see a chain emerge from Kimizuki's chest. With Saitō's plan relayed through the chain, and with Guren and Mahiru complying with it, Mitsuba questions if they are sure they can trust them. Mitsuba is envisioned when Yu is speaking with demon Mika about their family and also when Yu is forming a desire to protect his friends.

Natural abilities
Like all people who wield Cursed Gear weapons, Mitsuba has heightened strength. The demonic powered axe also allows her to generate from injuries that would be more serious to those without a cursed gear. She joined the Moon Demon Company at an age of thirteen, which suggests that she is highly talented in order to be accepted at such a young age. She shows exceptional strength and reflexes, easily cutting down vampires during one of the squad's first missions. Her agility assists her in avoiding explosive spell tags.

Cursed Gear

 * Tenjiryū (天字竜): A manifestation-type demon from the Dakini series. It takes the form of a giant battle axe. Despite it's colossal size, it can be held and swung as if it were much lighter. It is most effective at mid-to close-range. By cutting into the ground, Mitsuba can spawn multiple fiery demon manifestations and attack with them. However, where they are weak individually against stronger foes their function is then good as a decoy, and as coverage.

Seraph of the End: Vampire Reign
"Lieutenant Colonel Guren!! I don't understand!! Why are you assigning me to a squad full of rookies?! I've been part of this extermination unit since I was thirteen! I'm an elite!! Now, if I were extremely generous and gave this the benefit of the doubt, I could understand being assigned as their leader! But you said that sarcastic airhead Shinoa Hīragi is going to be squad leader! Explain that to me!"

- Mitsuba to Guren.

"It's morons like you... that I hate... more than anything! People like you... wipe out entire squads."

- Mitsuba to Yu.

"Who does that Yūichirō Hyakuya think he is?! Ignoring orders! Acting on his own! How could someone like him make it into the Moon Demon Company?! I won't stand for it!"

- Mitsuba to Shinoa.

"Damn it..! I'm lost!! The rest of you leave me and run!!"

- Mitsuba to Shinoa Squad.

"This is war."

- Mitsuba to Shinoa Squad.

"HEY!! You could at least give that the insult it deserves! Do I have to spell it out for you? I was utterly useless that entire battle! After all the big stuff I said, I didn't do a single thing! Once again... I couldn't save anybody. I... I... I'm still so weak. But despite all that... I'll be the only one promoted, just because I'm a Sangū. If you wanna laugh at me... go ahead and..."

- Mitsuba to Yu.

"H-Hey! Quit acting like you understand!! Someone died because of me, but I wasn't punished! I was totally useless in battle, but they promoted me! The only bad thing that ever happens to me is getting laughed at for being inferior to my elite sister!"

- Mitsuba to Yu.

"Okay. First, as I will be your instructor, you will call me 'Master."

- Mitsuba to Shinoa Squad

"L-Leave me and run!! You can't afford to waste time here!!"

- Mitsuba when she grabs onto Crowley's leg to try and delay him

"I... I-I'm not... I'm not going to be the weak link anymore!!"

- Mitsuba.

"You actually like doing dumb, kiddie stuff like riding on the roof? No wonder you and Yu get along so well."

- Mitsuba teasing Mika

"There is never anything 'correct' when you're dealing with the Hīragi family."

- Mitsuba to Mika.

"Ugh. You really are dumb. It's not worth it to stick your neck out to cover for someone like me."

- Mitsuba to Yu.

"Erm. Hey, Yu..? ...It made me happy to hear you call me family. Thanks."

- Mitsuba to Yu.

"You let yourself get possessed and I'll send you flying. Got it?"

- Firm words of encouragement for Yu as he heads to save Mika

"You sure we can trust them?"

- Asking Yoichi and Kimizuki if they can trust Saito, Guren, and Mahiru.

Trivia

 * The "Mitsu" part of her given name and the "San" part of her surname are both written with "三", the kanji for "three."
 * The name Mitsuba means "three" (三) (mitsu) and "leaf" (葉) (ha/ba), which literally translates to "three-leaf clover."
 * Mitsuba's surname Sangū means "three" (三) (san) and "temple, shrine, palace" (宮) (gū').
 * Mitsuba joined the Vampire Extermination Unit when she was thirteen.
 * In the popularity poll, Mitsuba earned 7th place at 1,002 points.
 * The author Takaya Kagami mentioned that Mitsuba has something awaiting her and that she feels the same way towards Aoi Sangū as Shinoa Hīragi feels towards Mahiru Hīragi.
 * Her future dream is to be a bride.
 * According to the Manga 8.5 Fanbook:
 * Interests/Likes: [Interests] How to be a good soldier / How to live in such a way that won’t bring shame to the Sangū House’s way of living / More or less her inferiority complex over her excellent older sister / Feminine power (she thinks she somehow needs to do a little more.)
 * Favorite Food: Types of wagashi (strawberry daifuku, kusa mochi)
 * What she looks for in the opposite sex: Someone she can rely on as a leader / Someone who is an even worse cook than her and someone who is trustworthy and brave