Guren Ichinose

Guren Ichinose (一瀬グレン) is a character in Seraph of the End, the main protagonist of the prequel story Seraph of the End: Guren Ichinose: Catastrophe at Sixteen and the manga adaption. Entering school accompanied by Sayuri Hanayori and Shigure Yukimi, he was wary of others learning about his capabilities since they were outright hostile to him on account of his family background. With thoughts of biding his time and undermining such house structures, particularly the Hīragi Family, he would be approached by Saitō and informed of the upcoming apocalypse event. He would be befriended by Mito Jūjō and Norito Goshi, along with Shinya Hīragi, where they were tasked by Kureto Hīragi of intervening against the Hyakuya Sect's plans.

While still a teenager, Guren's experiences continue in the sequel light novel series, Seraph of the End: Guren Ichinose: Resurrection at Nineteen. In addition, he is the tritagonist in the Seraph of the End: Vampire Reign manga series, which takes place eight years later. Guren is a Lieutenant Colonel of the Japanese Imperial Demon Army, and the leader of the Vampire Extermination Unit's Moon Demon Company where he is the squad leader of the Guren Squad (グレン隊). After retrieving Yūichirō Hyakuya he promises him revenge against the vampires who have taken over the ruined world. Working closely with Shinoa Hīragi he also arranges for Yu, along with Yoichi Saotome and Shihō Kimizuki to acquire black demon Cursed Gear weapons. Adding Mitsuba Sangū as the fifth member, Guren would have them join him in Shinjuku to repel a vampire invasion where he was overcome in combat by Mikaela Hyakuya.

Not hiding his knowledge of human experimentation, Guren is carrying out his own plans. Dutifully complying with orders to lead an attack on vampire nobles in Nagoya, there Guren would be possessed by his demon Mahiru-no-Yo and be involved with bringing a seraph into the world. Seeking out Shinoa squad, Guren professed he wished to resurrect all of humanity. With Shikama Dōji active and Saitō's emergence, Guren acted with his demons Mahiru, and Noya Hienma where his combat skills were used against allies once more.

Appearance
Guren is a tall, young man with medium length black hair similar to an overgrown wavy mullet, with slightly overgrown messy bangs parted in the middle and complementary violet purple eyes. He is considered quite handsome according to some girls who are infatuated with him. He is regularly seen in uniform based attire.

Catastrophe
As a student Guren wore the First Shibuya High Uniform, a black with a standing collar, with red trim which was also around the cuffs. Instead of the school emblem, he wore the Order of the Imperial Moon emblem on the left breast. When his squad was first formed, Guren wore the standard Japanese Imperial Demon Army uniform which consists of a long-sleeved black jacket with two rows of gold buttons on the front, and red details including the shoulder epaulets. A brown Sam Browne style belt passes diagonally over his right shoulder and holds a brown pouch on his left side. Along with that, he wears a pair of white gloves and a red standard belt. Guren also wears the uniform trousers with knee-high black boots which go over his trouser legging.

Vampire Reign
Sometimes his hair is slicked back during the midst of skirmishes on the battlefield, but more often is seen with slightly tousled hair, with bangs hanging over his forehead. Guren wears the standard Japanese Imperial Demon Army uniform updated for his taller self, which consists of a long-sleeved, double-breasted black coat with two rows of gold buttons down the front, with red details including, gores at the bottom, and stripes on sleeves. Other decorative features include golden and white fourrageres worn on the right shoulder, attached to a stylized cherry blossom decoration pendant at the center of his collar, and two bars with unit insignia medal below them on the left. Guren wears a pair of white gloves, a black on white armband on his left arm, and a similarly striped black and white web belt with a frog for his sword on the left, and a gold waist-plate. In addition, he also wears the uniform trousers with two white belts strapped around his left leg and black shoes.

In the manga illustration, he also wore a black cape or overcoat with a red lining. In the anime artwork, Guren is shown wearing a maroon coat with red ornamented sleeves. Anime and manga versions have in common the shoulder epaulettes and a gold unit insignia. While the shoulder epaulettes are primarily red in the anime, they are a mixture between black and beige in the manga. The anime version shows extra red markings and gold details. In contrast to the anime, the manga depicted the cloak to have beige for its insignia, and details spread all around the garment, with no markings visible.

Human
In his childhood days Guren's outlook on life was simple until Mahiru Hīragi entered his life. Aware of the barriers between them due to their family backgrounds, when he was forcefully separated from Mahiru and treated with contempt for being part of a lowly branch family, Guren felt guilty for being too weak in physique and power to not reach out for what he wanted back then: Mahiru.

He was strongly devoted to Mahiru Hīragi, displaying the strength and goodness of his heart. Even when she betrayed him multiple times, he couldn't leave her alone and keeps trying to save her. Indeed, when pressured with the death of Sakae, Guren showed he could not bring himself to actually kill her, opting to commit suicide with her, which failed. Even after Mahiru killed all his friends, as she was the only thing that was left, he didn't kill her.

Although he treats Mahiru-no-Yo coldly, as later on revealed Guren never let go of the guilt and sadness he felt over his failure in his childhood days. Along with the guilt for triggering the apocalypse to save his friends. Guren shows regret over what he had done to the world and now wants to undo it.

Guren had to learn the hard way that he wanted to rely on his friends again after the trauma he had experienced in his childhood. Due to his friends, Guren would become a wise leader who values teamwork, co-operation, and friends, determined to ensure the survival of the human race from demons and vampires. He actually cares a lot about his subordinates, and considers his friends to be his family, both before and after the apocalypse. When Yūichirō Hyakuya tried to join the Moon Demon Company, Guren refused until he made friends. Guren is also courageous and loyal to his friends, even to the point of ordering Shinya to abandon him and take command for the group in his stead, so they can escape, while carrying on with their mission.

"Anyone with a heart cries when a friend dies. But we can't afford to do that right now. We have a mission to complete."

- While troubled at others dying, he remains practical given the situation.

Guren sometimes appears to be indolent, but in truth, he really works hard just in areas other than official army meetings and instructing classes for examples. He keeps many secrets to himself, and has no difficulty lying about them. Concerning long term plans to dethrone the Hīragi Family, this, and his sleepiness, it is partially a result of a desire pressed on him upon being possessed by Mahiru-no-Yo. It is made clear when Guren is possessed, and his true desires come to light, that he wants to change the status quo and hierarchy. Willing to work with what should be sworn enemies, whether people or vampires hostile to him, Guren proceeds with plans that are beneficial in the larger picture. From his school days, not showing enemies what he is capable of, or what he wants, and allowing them to have a wrong impression of him has been a practice. Further long term, and forward thinking plans were acquiring the bodies of those others around him knew, to keep in storage.

Casual in his dealings with others, Guren is flippant even to ruling members of the Hīragi family where he thinks nothing of simply walking out a meeting he is not interested in. Laid-back, he also fends off Yu's surprise appearances, and thinks nothing of sudden unanticipated actions such as flooding a room with Mahiru-no-Yo's cursed gear effects. His displays such as this, and reminding Yu to not attack a superior officer such as himself are unpretentious, not done to impress, rather ascertain a situation such as who can handle cursed gear, or dismiss a tedious ordeal to him as fast as is practical. Often answering Shinoa's merriment with raillery of his own, he is not aloof in conversation despite his ranks and titles unlike his contemporaries. While appearing serious in administering a disciplinary, behind closed doors Guren informally speaks with Yu and shares with him his true plan in mind.

An effective commander, Guren locates the leaders on the battlefield to engage them directly. Guren rallies soldiers with the harsh truth many may not survive but the goal is not to come back alive, it is to be victorious no matter what. To help others distinguish when it is okay to be facetious or serious, Guren will issue a reality check involving a practice fight, where he holds back to prevent them injury, to lay bare the consequence of failure. As a fighter, Guren relies on brute strength involving powerful strikes and emissions from his cursed gear. He makes use of relying on his team, and luring others into traps. Sheathing his sword, to deliver an unexpected spell tag with other feints are used to give himself an advantage. Pleased to be in control of a situation, Guren will also remark on how things are going his way.

"If Mikaela kills you to come back to life... ...Do you think that he'll want to go on after you're gone? What about if the shoe was on the other foot? Would you want to come back to life if it meant killing Mikaela?"

- With what he knows of how Yu and Mika matter to one another, Guren uses this to dissuade Yu from allowing his body to be taken over by what he regards as a demon.

His overall pleasant demeanor, and repeated claims of putting family first, with good natured intentions of wanting to help others is extraordinarily successful in allowing a conspicuous manipulative streak to go unchecked. Comments on a prophecy masked his alliance with Ferid when locating Yu. He justifies human experimentation due to the state of the world necessitating it to survive, and can become a demon to mitigate any qualms he may feel about serious wrongdoings. Building an extensive rapport with Kureto over time enables him to talk his way out of the accusation that he is gathering black demon holders for a coup, then continue on his way with a mission. After inflicting serious injuries on others, Guren can also literally get away with murder after murdering a sibling with the pacifying incentive that everything will be alright once he resurrects everyone. A tearful and heartfelt display evidently makes it all the more convincing.

Namanari
His kindness is the reason for why Guren has not been completely honest with his squad whenever they are around him. Even more secretive, Guren hid his second personality where even one of his closest friends Shinya was unaware of it. Remaining nice was another reason for why his original personality had yet to be fully taken over by his second, demonic personality, and continues to exist. Nevertheless, he has since kept his own emotions in check on a daily basis, carefully maintaining a positive image so as to not worry them.

"Get your disgusting hands off of me, Bloodsucker. Touch me again and die."

- Demonic Guren about to deal with a noble who was beating him.

Guren first turned into a Namanari when Noya took control of his body. When Noya took over, Guren personality drastically changes, although he had some control of his body as shown when he warned his friends to get away from him. He would nonetheless slaughter anyone in his way, as Noya was filling Guren's head with the desire to kill. When Mahiru-no-Yo takes over his body, his Namanari personality seems to have evolved, as even his voice started to become more feminine tone resembling Mahiru's. In the anime when he is overtaken by his demon blade, Mahiru-no-Yo. his voice remains the same, although Guren's personality still changes. According to Ferid Bathory, it happens more often than others know, and his demon side is capable of hiding his true nature from his close friends. Guren is described as being a Namanari, a human with two souls in his body, just a single step away from becoming a complete demon. When Mahiru is in control of Guren's body, he becomes utterly ruthless in the pursuit of his goals. It is not just those who opposes him that he will attack, Guren will rapidly move round and murder anyone nearby, friend or foe, even if it is one of his close comrades. He stabbed Shihō when he moved to try and rescue his sister, and at seeing Yu his reaction was to try and slash him, before stabbing when he got another chance. Guren does not appear to regard it as vampires or humans, friend or foe when possessed, rather identifying them all as sacrifices to offer for the Seraph of the End experiment that he has to kill as fast as he can.

"Do it, Yu. Break their taboos. Only someone so arrogant who desires to be loved by everyone... Only you can do it."

- Possessed Guren encouraging Yu to fall from an angel and become a demon.

After Mahiru-no-Yo and Noya separate, truly turning Guren into a Namanari bearing redoubtable demon horns, Guren has shown previously unseen lenience by sparing Shinya and the rest of his squad. While articulating that he was a demon, Guren showed he still cares for them by keeping them restrained. Committed to plans that only he knew, Guren set about using chains to stab into his squad to sap them of power to supplement his own. Announcing that he would keep them safe, Guren opted to deal with the problem of the First in Shinoa's body on his own. His cunning was not diminished, indeed as a namanari he anticipated a betrayal from Saito, and as ever himself, Guren remained in control in the middle of a tense situation and was ready to enact a double-cross on a traitor. In this state, Guren took into account a time limit on his enhanced powers, and was analytical in evaluating his own strength. Not satisfied with the force of his tremendously powerful strikes, Guren has his demons returned to his body to conserve power.

Story
Guren Ichinose is waiting for Yūichirō Hyakuya outside the underground city he escaped from. Deeming him useful in the fight against vampires he offers him a chance of vengeance against them. Four years later, Guren would arrive with his squad to repel a vampire attacking him. Guren required that Yu work well with others and had Shinoa Hīragi assigned to monitor these efforts. Along with Yu he would have Yoichi Saotome and Shihō Kimizuki acquire black demon cursed gear weapons. Appointing Mitsuba Sangū as the fifth member of Shinoa squad, Guren would task them with clearing a vampire lair and freeing the humans within.

With the city of Shinjuku coming under attack from a vampire invasion, Guren gathered his own squad to him before targeting the leadership of the operation. Coming into conflict with Mikaela Hyakuya, his advantage gained thanks to his squad would end with the intervention of Ferid Bathory. Ordering a retreat with the arrival of additional vampire nobles including Crowley Eusford, he would then be restrained. Witnessing Yu transform into a murderous one winged being, Guren would declare his trump card had brought the time he needed for the main force of the Japanese Imperial Demon Army to arrive, for the human forces to prevail.

Conscious that Yu might defer to the Hīragi Family's orders, Guren reminds Yu who saved him. He also agrees to help Yu reclaim Mika. Gathering forces for a campaign to target vampire nobles in Nagoya on Kureto Hīragi's orders, he would then take part in a rescue attempt when prisoners were taken. Along with Shinya Hīragi he would engage Crowley before being captured by Chess Belle and Horn Skuld too. Succumbing to possession by his demon Mahiru-no-Yo, he would share the location of an experiment taking place at Nagoya airport with Krul Tepes when he was seen as Mahiru Hīragi's messenger. There he would murder both his own soldiers and vampires to allow a seraph entry to the world.

Leading an army with Kureto he would sack the vampire hold of Sanguinem. Seeking out Yu with Shinoa squad, Guren detailed plans of resurrecting all who had died in the apocalypse. Stating that Mika could leave if he wanted to, Guren specified that Yu was vital to these plans. After formulating and preparing for a plan to do so, fighting against Ky Luc resulted in Ferid being freed from his sunlight exposure torture. Recuperating at his residence, Guren would reveal another seraph kept there and help deal with the Horsemen of the Apocalypse that were summoned.

Aware that Kureto meant a succession change, Guren travelled to Shibuya. With Shikama Dōji becoming active as a result of events there, Guren would see Shinoa possessed by him. With the Hyakuya Sect led under Saitō reacting to the first by assaulting Shibuya, Guren determined that this was the time to betray everyone. Partitioning Mahiru-no-Yo into the Mahiru and Noya constituents, Guren would be able to generate chains to sap the strength of his squad to augment his power to an even greater extent. The combined strengths enabled him to participate in Saitō's battle against the first. Ready for Saitō's treachery, Guren double-crossed him in turn with assistance from Ferid. Seizing the three sinful keys in the vicinity, Guren was able to seal Shikama Dōji.

With his enhanced powers diminishing with time, Guren sought out Yu and once Mika arrived he attacked them both. Backing them into a corner resulted in Mika sacrificing himself where Guren thought that he was turning into a black demon. After joining Krul who was with Shinoa squad where the first had regained control, Guren hurried Yu to prepare to gain Mika as a cursed gear weapon. Preparing a spell circle, Guren was not sure whether to proceed with his plan after Yu heard Mika's voice, uncertain of whether it was a plot by Shikama Dōji. Pressing ahead, Guren convinced Yu that Mika was a demon who had forgotten about him. Contacted by Saitō to resume their plan, Guren complied at once.

Natural abilities
Adept with prior knowledge of experimentation since he was a teenager, Guren has proven himself to be an intelligent scientist, capable of developing Cursed Gear during adulthood. Due to this, he has even managed to create a method that comes with a very high rate of success for the development of humans who can bear Black Demon Series weaponry. Guren is also an exceptional strategist and leader, with him being typically the leader of any team he is in, due in part to gathering a circle of friends who serve him out of house or rank loyalty, and from helping them. He is known for having backup plans, such as giving Yu the drug to activate his Seraph genes in case they were cornered. Very analytical, Guren is able to quickly deduce how to counter a current predicament, such as ordering the group to retreat in the face of too many superiorly powerful foes. Back when he was still a teenager, even Kureto acknowledges the great intellectual, political-like nature of Guren's capabilities. Having known each other at the span of about eight years, Guren was his right-hand man in carrying out his missions. Guren is also adept with his knowledge of the five-man battle formation called Moon Demon Company, which is mainly used as a tactic for defense within his squad. He is highly proficient in deceiving others, as shown by how no one, not even Shinya, with only Kureto and Ferid being the only individuals aware, knew of his demonic personality until he embraced it in the open.

Highly skilled in martial arts, Guren often implements hand-to-hand attacks effectively while engaged in swordplay to easily batter aside enemies. He fairly quickly defeated Shinya in hand-to-hand and even could dominate Mika as a true Vampire wielding his sword while greatly empowered physically by Mahiru-no-Yo for a while using only his bare hands.

Guren is an outstandingly proficient combatant, specializing in swordsmanship among his many forms of combat. Born with outstanding talent among the Ichinose Family, Guren's combat skills marks him as among the finest fighters in the army and he can easily hold his own and triumph in a fight even against those with superior physical power, or other highly skilled combatants with great might. During his teen days, Guren once managed to evenly duel Kureto while apparently holding back, with Kureto having to use the full power of his Cursed Gear to overpower him. Even with this, Guren still put up a brief fight and was able to slice off Kureto's arm. Since he is not an ordinary human anymore, Guren was able to fully recover one of his cut-off arms, and survive powerful vampire attacks from the seventh progenitor, Ferid Bathory, both when they met when he was sixteen, and later, on the battlefield as an adult which surprised him.

One such display involved Guren being able to kill several common vampires with a single strike. He can fight Mika evenly, who has the blood of a third progenitor and wields a first-class vampire sword. Indeed, with assistance from his squad, Guren almost came close to defeating Mikaela had Ferid not intervened, and had Mika not been holding back. Later as a Namanari, Guren calmly overwhelms Mika even after he fully became a complete vampire, with the power of his Cursed Gear aiding him. Another instant is when he bypasses Yu's defense in the mock battle to get to his squad members, defeating both Shinoa and Mitsuba first despite it being her five-men squad against a three-men squad with Mito and Shinya present.

Magic and Spells
Guren also specializes in other combat assets such as the use of magic and spell tags, known for having particular abilities in it even among the Ichinose Family and he is proficient in using it strategically in combat. Guren also holds great knowledge in spell casting, as shown by how he was able to see through one of Goshi's illusionary techniques and anticipated Mito's Vajrayaksa Curse before easily countering it.


 * Fudo Myo-o spell: Guren is capable of skillfully using enchantments on spell tags and talismans since late teens. At the age of sixteen, he can implement a talisman on the sword to augment the weapon's cursed power and ability. As a result, from synchronizing the talisman with the blade itself, this created an explosion to unnaturally occur on the enemy's body to inflict greater physical damage. In doing so, Guren can also successfully implant one of these spell tags on the targets' head whenever they are caught off-guarded or if the chance presents itself. In such cases, this type is an ancient one that causes an explosion to occur after a few seconds or apparently at will before detonating.


 * Illusion spell: While fighting the demonic Yu, and Mika, as a demon himself, Guren used a spell that allowed him to create an illusion of himself. This could sustain extensive damage and was successful as a ruse so he could get close to them. The spell was notably convincing enough that Mika, who could see through Goshi's illusions, could not notice it, and Yu's levitating weapons that could hone in on a target also sought out the body double. The Ichinose family and particularly Guren had special incantations such as a talisman placed on the scabbard of his katana. When he activates the incantations through a talisman for the blade, it begins to make the sword glow brightly crimson red in color.


 * Paralyzing spell: An incapacitating spell within a spell tag was able to paralyze both Yu and Mika after being physically placed on their backs.

Equipment

 * Kujakumaru: This blade goes by the name of Kujakumaru and is already wielded by Guren Ichinose at the age of fifteen. It was a Guren wielding Kujakumaru LN.jpg heirloom that had been passed down from generations in the Ichinose Clan. Kujakumaru was a sword that had been sealed with the curses of those who had been beheaded by it. The sword was able to prevent the enemy from absorbing the impact of an explosion created by a talisman that had been put in place on the blade, which was supposed to resist any of the Hīragi Family's curses. Once the seal had been lifted, the enemy will soon become cursed by this weapon, with the effects of their body becoming red. As a result, the curse will eventually destroy the enemy's body, where their flesh be torn apart and atomize. The sword is cut in half after Guren's first battle with Mahiru.


 * River's Edge: An enchanted blade owned by the Ichinose Clan. After Mahiru destroys Kujakumaru, Guren begins using this sword in its place. When Kureto captures and interrogates him, he takes this sword and returns it to the Ichinose Clan before Guren receives Hoarfrost instead.


 * Hoarfrost: Guren was given this enchanted katana by Kureto after he swears loyalty to him. It vibrates and emits a high pitched ring when Guren drew it from its sheath, and was then filled with the desire for slaughter and bloodshed. According to one of the many tales about the blade, it cut down a thousand demons in a row without getting a single nick.

Cursed Gear

 * Noya (ノ夜): A demon who formed a contract with Guren, given to him by Mahiru and becomes his demon weapon in the form of a black katana. Guren can call Noya to have the weapon fly back to his hand whenever they are separated. It is revealed that Noya is a possession-type demon of the Black Demon Series as it is mainly concentrated on enhancing Guren's physical abilities similar to Mahiru-no-Yo. Noya can increase Guren's strength by using his desires as sustenance. Eventually, after Mahiru fuses herself with the demon, Noya transforms into the merged Mahiru-no-Yo. This was a reversible process, where some time later Noya managed to erupt from Mahiru's body to entice, and then make Guren into a full demon.


 * Mahiru-no-Yo (真昼ノ夜): A possession-type demon of the Black Demon series that Guren wields as his cursed gear. The physical weapon remains black katana, like Noya, but now has a glowing, crimson red streak that is outlined under the blade ridge.Glen's Demon Possession.png Mahiru-no-Yo can significantly amplify Guren's physical abilities, and calling out the joint beings name would increase his power to ever greater extents. Stabbing into a foe can cause wounds to fizzle, where the curse can be activated to have them entirely dissolve. If Guren wishes to, he can invoke the demon's real name to have them possess him. This would cause Mahiru-no-Yo's apparition to appear and enshroud the blade and the arm wielding it with streaks of intense flames. Guren would be able to launch these fires at his opponent with one slash, where they are strong enough to generate an explosion in the midst of its vicinity.

Additionally, Guren can utilize the power of the demon weapon for other miscellaneous purposes. Merely drawing the katana from its sheath alone seeps a blackish flowing mist made from within in and out of the blade where it fills enclosed areas like a classroom with its immense demonic auras. Within the power's vicinity and range, victims pass out unconscious on the floor if they do not have the strength or willpower to weather it. However, this enervating infliction is limited if the targets have high psychic resistance, used wards, or are a potential candidate for the Black Demon Series, where it is largely ineffective to them.

Not only does it strengthen his own abilities and power physically, Mahiru-no-Yo can also be used to devour an enemy's attack. If Guren was on the defensive side, he would then call on the demon blade's name to assist him in battle when he was knocked far back and being sent flying to the ceiling. He will then used the demon's power and ability to cushion his physical impact for safe landing. This was only while the appearance of demonic auras became visible from behind Guren, materializing onto him in sparks gradually.

"The life-absorption barrier is getting weaker and weaker. Add to that the need to split the power between you two... ... and it's no wonder my strike was so flimsy."

- Speaking to Mahiru and Noya whilst he appraises his current levels of power, and his views with his attack that expanded across a city.

Once Guren is possessed by Mahiru-no-Yo, the blade would appear to have a mind of its own. The blade unsheathed itself from the scabbard and then proceeded to move around on air swiftly, where it had the swiftness and power to behead a noble vampire. After this transpired, Mahiru-no-Yo appears as a ghostly apparition backed with a mass of demonic aura, hovering over Guren while his katana is equipped under them. Powered by vampire, human, and progenitor blood, the blade took on a complete red appearance. Something similar occurred when Guren used a talisman to turn the color of a non-cursed gear's blade crimson.

Later, Mahiru herself becomes a Cursed Gear weapon and generate power to Guren. She is also capable of various effects such as poison other Cursed Gear wielders.
 * Mahiru! Moon Demon Stance!: Shadows appear from the weapon, and Guren becomes cloaked in fiery manifestations of them.


 * Mahiru. Moonlight Stance.: With his left arm raised behind, Guren holds his sword near the around for multiple ovals to appear around him.

Demonic powers
When Mahiru and Noya separate, Guren becomes a demon with large horns with a vast increase in power, and is noted to be no ordinary demon. Guren can release an overwhelming pressure capable of easily flooring and pinning down his whole squad completely, which appeared to take a great deal of resistance to overcome as Shinya demonstrated. Chains were released from Guren that were capable of draining power from his debilitated squad. In this existence, Guren could supplement his power through various means. Guren's physical strength and speed increases to the point where he can easily deflect all of Shinya's ranged and close-quarter attacks in his own demon state and soon defeat and severely injure him. Guren was able to blitz past Kimizuki and Yoichi to easily kill Mirai before they could react, then bound away great distances. Working with his demons, Guren could mount an attack on the First, where his reflexes could be use to hold sinful keys to seal Shikama Dōji. Capable of overpowering Mika and Yu's guard with a single slash to send them flying, Guren's strike cut through several buildings, despite not being at full power by that time. His endurance and stamina is such that he was able to endure Mika forcibly biting and draining him of much of his blood and remain conscious.

Book 1
"When I was young, I was sure all of my dreams would come true. I could be with the person I love. I could have the things I wanted. I could live happy. It all seemed so easy. It really did."

- Six-year-old Guren's point of view.

"She was sitting so close I could hear her breathe. I liked the sound. I liked her voice. I liked listening to her heart beating next to mine. I liked everything about her."

- Six-year-old Guren's point of view

"I belonged to a lowly branch clan. But from my place, down in the dirt, Mahiru shone like the sun."

- Six-year-old Guren's point of view.

"…Power. I’ll never get the things I want in life…unless I have power."

- Six-year-old Guren's point of view.

"Haha. Actually, I said it because you two are underestimating the Hīragi Clan. I’m gonna repeat this one more time. Don’t get reckless. Not even for a second. We have to be on our guard at all times. Apart from us three, no one at this school is loyal to the Imperial Moon. They’re all enemies. Every single one."

- Guren to Shigure and Sayuri.

"I decided before today that any opponent who sees my full strength needs to die. I’m giving you five seconds. Go back to your masters and tell them the Ichinoses won’t play ball. I’ll count: Five…Four…Three…"

- To Makoto Kijima (Saito).

"You’ve grown up. You’ve become strong and beautiful."

- Guren to Mahiru.

"There it is. 'The end of the world.' The Thousand Nights is just another fly-by-night cult, isn’t it? Let me guess: Only true believers, who join your religion, will be saved. Am I right? Our clan pulls the same kind of tricks. So do the Hīragis. Everyone as the same gimmick. Did you think that was all it would take to trick me into joining you?"

- Guren to Saito.

"I know better than to trust someone who can’t keep his trap shut."

- Guren to Shinya.

"For my part, I’m not interested in being a puppet for the Thousand Nights. I’ve already had enough of bowing my head. My answer is right here! I’ll destroy anyone who tries to control me!"

- Guren to Saito.

"Kujakumaru…release!"

- Guren summoning Kujakumaru.

"Look at what’s happening to you, Saitō. Do you know why you’re glowing red? The curse is feeding on you. The curse changes you, and then it devours you. Once it has finished consuming you, you’ll be trapped for all eternity inside the sword."

- Guren to Saitō.

"I think you’ve gone mad. Tell me, how many people did you sacrifice to create that blade? How many lives were lost to your experiments?"

- Guren to Mahiru.

"Hmph. I don’t know why you’re acting so friendly all of a sudden, but I don’t think I like it."

- Guren to Norito.

"You’re right, I’ve got no reason to thank you. What I was gonna say is, just stay away from me. I don’t need any friends."

- Guren to Mito and Norito.

Book 2
"I’m patient. I was born that way. Unlike a certain brat I know who takes every chance he gets to show off."

- Guren to Shinya.

"Tell her I don’t like being manipulated. By anyone. Tell her that she’s a fool, and if she really thinks she loves me she should stop playing games and tell me what she’s planning."

- A message to Mahiru.

"...betraying the Thousand Nights…the end of the world…our destinations are the same… This is all starting to sound like some grand romance novel. What are you planning, Mahiru…"

- Guren's thoughts.

"…Ngh. You son of a bitch. Why did you even spout all that stuff about wanting to see who was stronger?"

- Guren to Kureto.

"I don’t care about you enough to bother laughing at you."

- Guren to Mito.

"So I’m actually strong. So what? What difference does strength make when you’re born an Ichinose? You’re from the great and mighty Goshi Clan. And that redhead back there is an esteemed Jūjō. But what am I? As far as the Hīragis are concerned, I’m just an Ichinose mongrel. No amount of strength can change that."

- Guren to Norito.

"I know you’re ready to sacrifice others. Aren’t you? Mahiru…"

- Guren's thoughts.

"What you should really be angry about is how weak we are. They can torture us and we don’t even have the right to get angry about it. They almost killed my father. It’s not the Hīragis who are the problem. It’s our own lack of power."

- Guren.

"You don’t have to protect me. I don’t need to hide my strength anymore."

- Guren to Shigure and Sayuri.

"Of course, the Hīragi army is a pack of fools. It’s possible the area’s been poisoned and they all just marched in to their deaths without noticing. If that’s the case, then there may not be enemies on the ground after all."

- Guren.

"And what do you propose we should do? With so little information, any in-depth strategy will just trip us up. We can spend all the time we like talking about what we think might happen and how everything should play out. But we can’t get wrapped up in some foolish plan based on wishful thinking. What we need to do is kill any enemy that shows up. And if we can’t kill them, we need to at least try to make it back out alive."

- Guren to the squad.

"As squad leader I only have one order for you. Drill this into your heads. I don’t want you to think of anything else. Nothing else is important, do you understand? The order is…don’t die. No matter what else happens, do not die. Ready… The mission has begun."

- Guren to the squad.

"Mahiru… You’ve got to stop this research into cursed gear. It’s no good. This is the kind of power that will make fools of us. It will control us."

- Mahiru to Guren.

"We’ll think of another way. There’s got to be something else, another path…"

- Guren to Mahiru.

"This time, I’ll protect you. Come with me, Mahiru."

- Guren to Mahiru.

"Hmph. Haven’t you ever heard of 'The Tortoise and the Hare'? If you keep rushing forward at this pace you’re going to destroy yourself."

- Guren to Mahiru.

"I can save you now. Throw away the sword and come with me."

- Guren to Mahiru.

"The war began for me when I was just a little kid."

- Guren.

Book 3
"If we start conducting human experiments, where will it stop? New magic, new research, new powers. Power, power, power…. And then what? What happens after we turn our own comrades into human guinea pigs? Will we be swallowed whole by our own lust for power, or will the Hīragis crush us beneath their boots? Either way, it’s a disaster in the end."

- Guren to Mitsuki Iori.

"I want you to avoid human experimentation as much as possible… If we’re going to do this, we’re going to do it with our reason intact."

- Gurn to Mitsuki Iori and the other Order of the Imperial Moon Aichi scientists, giving them permission to study the demon’s infection.

"Hmph… So an angel is going to alight at Christmas, trumpet in hand, to kick sand in the world’s face? You gotta be kidding me. This is modern-day Japan we’re talking about."

- About Mahiru’s prophecy.

"At your level, do you think you’d even have the chance to kill yourself? Don’t underestimate the Hīragis. If the two of you knew what was going on, I would never let you leave this compound again. I’d find two other guards to serve me. Do you understand? If you want to stay by my side, then keep those ears covered."

- Guren to Sayuri and Shigure.

"What can I say? I’m just a loser, born and bred. I’ve always got to watch out for who’s going to kick me next."

- Guren to Shinya.

"Jokes are supposed to be funny. I guess you’re so used to being kissed up to that it’s rotted your brain."

- Guren to Kureto.

"I guess I can trust you a little after all…"

- Guren to Shinya.

"No, I am going to save you."

- Guren to Mahiru when she begs him to kill her.

"We’re together right now! I’m here, with you, right now!"

- Guren embracing Mahiru.

"For now… I don’t want you leaving my side. No more talk of things being too late. I’ll find a way. I’ll save you…"

- Guren to Mahiru.

"Dammit… Just be quiet. Isn’t it obvious how I feel? Look at what I’m doing. You know I shouldn’t have come here. You know I shouldn’t be touching you. So why do you think I’m doing it?!"

- Guren to Mahiru when she asks if he still loves her.

"Don’t ‘maybe’ me! Come out of this alive and you can figure out how you feel later. Love won’t mean shit if you die!"

- Guren to Mito.

"Ha… Haha… Ahahaha… Okay, Mahiru, I get it. I give up. I’ll become a hare, too. A demon. But I won’t be like you. I won’t give up everything. I won’t stop being human."

- Guren to himself.

Book 4
"I’m giving up my humanity so that nothing else will be lost!"

- Guren to himself.

"If the outcome is the same either way, then I choose to move forward."

- Guren to Noya.

"Rrrraaaaaaa…. Hahahahaha… Blood… Give me blood… I’ll kill them all! I’ll kill everyone who gets in my way!!"

- Possessed Guren.

"What’s the point of trying to deny the truth with your little fuda? Those desires inside you, those are the real you. You can’t deny that!"

- Guren to Shinya.

"So? My life should have ended today. So what if I get betrayed in the future? What other lives do I have to lose?"

- Guren to Noya.

"I told you I would protect you. But I can’t. I’m too weak. It’s my fault. But…at least, we can die together."

- Guren to Mahiru

Book 5
"That’s not true! This isn’t your fault! Goddammit, Kureto! Quit fucking around! You don’t need to do this. You know I’ll act! Let my father go right now!"

- Guren to Sakae and whomever is listening in.

"We won’t let them execute my father… We’re going to do everything we can in these next two days to eliminate Mahiru."

- Guren to Shigure and Sayuri.

"I started regretting things a long time ago."

- Guren to Kureto.

"Even as I am… I have friends who believe in me. I won’t betray their trust."

- Guren to Noya.

"If you’re not one of my friends, then become one. That’s an order. I want you to be my friend."

- Guren to Noya

Book 6
"What do we have to live for? …We’ll never be more than slaves. No matter how hard we try, nothing ever seems to go our way."

- Guren to Sakae Ichinose before his execution.

"Dad! …I’m proud that I was born your son."

- Guren to Sakae Ichinose immediately before the execution.

"I can do this, Dad… Don’t worry. I can do this. I can be the son you hoped I would be. Just keep watching over me."

- Guren to his father’s decapitated corpse.

"Then, I’ll tell you the truth. What your father said is true. We’re dirt. Accept it. It can’t be helped… But that’s only temporary. So no more complaints. Shut your mouth and follow me, got it? You do that, and I’ll lead you to that better future you’ve been waiting for."

- Guren to Makoto Narumi.

"You’re included in the list of people I want to protect."

- Guren to Mahiru.

"Listen up, everyone. I’m going to try contacting Mahiru now, to ask her for help. Chances are, the Imperial Demons will be tapping the call. So even if we manage to stop the world from being destroyed, we’ll probably be accused of treason for what I’m about to do and be put to death when this is all over."

- Guren to his squad.

"I thought that’s what you would all say. If we make it safely to Christmas, let’s spend it together, playing video games and eating cake. Chocolate, marron glacé, and strawberry shortcake."

- Guren to his squad.

Seraph of the End: Vampire Reign
"Nah. He's not actually my kid. But... I did come across him being held prisoner by vampires, so I decided to nab him. Now, he's such a pain in the ass that I wish I hadn't."

- Guren to the city guards about Yu.

"Hah! Hell no. You're still a weak little brat. Anybody who's so dumb that all they can do is think about their own personal grudge all day isn't going to be able to protect anyone... I told you, being strong isn't just about being good with a weapon."

- Guren to thirteen-year-old Yu.

"Something you want to protect. Friends. Comrades. Family. Pick any or all of the above... but just find them. If you don't, you'll be a weakling forever."

- Guren to thirteen-year-old Yu.

"Yes, you did. Unlike me, you're still nice. No matter how much you try, you won't be able to live only for revenge."

- Guren to thirteen-year-old Yu.

"That doesn't matter. Strength alone is not enough. Make friends. Find companions. Don't try to handle everything by yourself. Because if you do... when the demon sinks its claws into you... it will swallow you whole, and you won't be able to come back. Anger and impatience are a demon's favorite snacks. As you are now... you'd be devoured by your own desires and turn into a demon yourself."

- His advice to Kimizuki.

"Ugh! Dealing with idiots can be so exhausting. Still... Things are about to get a little more interesting."

- Guren about Tenri Hīragi.

"If you're not strong enough, you die. That's the way the world works now. We aren't holding hands and playing house here."

- Guren to Sayuri.

"You have talent. But you feel guilty because you couldn't save your sister. That's sapping your desire to live. But today... you've found enough reason. Your reason to live now... is to protect the ones who saved you today. Your friends. Revenge? Don't let something so petty consume you. That goes for you too, Moron. Forget your old family. Because you have a new family now. Put your life on the line for the ones you see before you. The past is gone. There is only the future."

- Guren to Yoichi, Yu, and Kimizuki.

"Oops. I missed their commander. Ah well. Once we control this point, we'll have have won anyway. Hey, Vampires! Was all that human blood you drank today tasty? Sure hope so... because that was your last supper. Here we go. Give me more power, Demon Blade: 'Mahiru-no-Yo'."

- Guren's pre-battle speech.

"So then, if I told you we're using him in our experiments, would you be angry? Humans are weak. Fragile. Now that the world has ended, what do we have to do to survive? What do we have to do to kill vampires? To eradicate the horsemen? Your sister, Mahiru Hīragi, invented Cursed Gear. How many people were sacrificed in that long process? Without it... do you honestly think humanity would be able to survive? Understand? So quit spewing idealistic crap at me, Little Girl. Or, what... Are you falling in love with Yūichirō?"

- Guren to Shinoa about Yūichirō.

"You're wrong about one thing, though. I'm not your friend. [I am] your superior. The guy you owe your life to. Your surrogate father. Put all those together, and I'm practically a god to you. You can even call me 'papa' if you want."

- Guren to Yu.

"Sheesh. Did you have to go on a stupid rant about the obvious, you idiot? I already told you... Everyone standing here right now is family. That includes me. Family... works together to bring back family."

- To Yu and their squad about Mika.

"Shaddap. I'm not that dumb. I'm scared of who I could lose on this mission. But... we have to answer the call. If we fail, humanity dies. And so, Shinya. Goshi. Mito. Sayuri. Shigure. I want to complete this mission with as few casualties as possible. For that, I ask for your help."

- Guren to his squad and Shinya.

"It's your punishment. Shinoa. This is your squad. I'm doing you a favor and teaching you that even a little mistake could kill them.... You don't get it. You've never had anyone important to you before. You don't know what it's like to fear losing someone. But now things are different. Even a tiny mistake is enough to kill. Your little pranks could cost your family their lives."

- A training exercise of sorts for Shinoa.

"Don't give up—Don't let the fear win. There's still a chance to pull out of this. Vampires don't kill off their livestock all willy-nilly. Make a little show of resistance... Then talk. Just give them a little dribble of info to lead them to Shinjuku tonight... and Kureto should handle the rest."

- His thoughts while being interrogated.

"Mahiru is dead. I couldn't save her."

- Guren to Krul.

"No, not yet. Guren. Sleep. Do not wake up yet. If you wake up into this, you will be scarred for the rest of your life... Ha... Ha ha... Yes... Everyone is a sacrifice..."

- To himself after seriously wounding Yu.

"A mere ten years. But... If that means I'll get to see my friends... and have my family smile at me one more time... I... will shoulder this sin."

- Guren's recollection about when he revived his team from the dead and triggered the Apocalypse.

"If I don't win, I can't save him. So I'll win. Simple as that."

- Guren to Mahiru.

"Good question. That is one I wondered about for years. I thought if only I could figure out who was pulling the strings... and then go beat them, that would somehow solve everything. I thought that we suffered because the Hīragi Family existed. I thought they were the ones who were holding us back. If I got stronger... If I got smarter... Then I thought I'd be able to reach out and make what I wanted mine..."

- Guren to Shinoa Squad.

"In the end, Kureto was the same as Mahiru... Born with Hīragi blood, they struggle. Fight. They try as hard as they can to walk a path as close as they can to get what they believe is right."

- Guren to Shinoa.

"I'm trying to resurrect all of humanity. Everyone I killed... I want to bring them all back."

- Guren's answer to Shinoa Squad.

"Me? I'm not much of anyone. And that's why I couldn't do anything before. But this time, it's different. This time, I will stand at the forefront of the whole world."

- Guren to Mika.

"Without Yu, you are alone. And anybody who’s alone is easy pickings. You can do nothing on your own."

- Having to demonstrate to Mika how it's better they work together.

"Ugh, gawd! We're only up against demons and the first and other freakin' monsters. And we've already had our butts handed to us. How can we not handle them now? Sheesh!"

- Views on the aftermath of battles and their participants with Saitō, Shikama Dōji, Yu and Mika.

"Yu. Mika is a demon. He's forgotten all about you. (Yu replies: "But he called for me..." and Guren responds) He's forgotten you. Tell yourself that. It's just like when you got Asuramaru to submit. He's going to attack you. Demons attacks humans. That's just what they do. Lose, and he'll possess you."

- Doubling down on his course of action and insisting to Yu that Mika is a memoryless demon to defeat despite Yu hearing Mika and that Guren knows there are other methods for one to become a demon as with the case of Mahiru.

"Exactly. Don't forget that you count as part of the family too. You're Mikaela's family. Take better care of yourself. Understood?"

- Guren tells Yu to live for Mika.

"He'll be powerful. He's the first's son, after all. He's more powerful than any black demon."

- Talking about demon demon.

"Yu. Do it right this time. Asuramaru's no pushover, yeah, but Mika is probably even more powerful. It's possible he could possess you after only one hit. And if you lose it's game over. For all of us. Mika won't be saved. You won't be saved. None of us will be saved. Everything will go exactly as Shikama Dōji planned."

- Guren reminds Yu why he should save Mika.

"Listen, Yu. Your enemy is powerful. Failure is unacceptable. Don't get hit. Not even once. And don't hesitate to strike. Over and over. That's the only way you can win."

- Instructing Yu to attack Miku without thinking.

"Quit crying, kid. That's the spirit."

- After training with Yu when he was a child.

"Okay! Good to see you back! I'll even compliment you on it!"

- The announcement after Yu, with Mika as a demon, then Kimizuki and Yoichi have returned, Guren is holding three sinful keys.

"I was just adjusting my speed too. I'm already one stage faster."

- Detailing to Mahiru on his battle status.

"Dammit. I gotta get him off of me! Mahiru!"

- Speaking his intent and calling for Mahiru to help get Yu off.

"Okay. I'll tell you the truth."

- Told that he can tell lies to Yu where his plan is concerned, then claiming he will tell the truth.

"Ugh... I said I'd tell you everything when we got to where we're going. It's a long, complicated story. Wait until we get there. I keep telling you, it'll make more sense if I can show you something while I explain..."

- Telling Yu information will come once they reach a destination.

"Seven. There were seven coffins already there."

- Answering how many people he revived and revealing there were prearrangements.

"I could've foiled their plans that day. All I had to do was give up on Shinya and the others. Destroy the coffins. Let them stay dead. That's all I had to do."

- Detailing how he thinks the Demon Army's plan could have been prevented.

"No. I did it. That's the truth... ...And there's no changing it. If I'd let myself die along with Shinya, Mahiru, and the others that night... ...I would not be here right now."

- Taking the blame rather than accept the Demon Army would have done it anyway.

"No. This is the path I chose for myself. It's not what Shikama Doji planned."

- Rejecting Shinoa's idea that resurrection was a part of the First's plan.

"Uh, no. It's not nearly so convenient. There's a stupidly massive price."

- Revealing there is a price involved with resurrection even is seraphs were controlled.

"The price to resurrect him is the same as what it takes to bring back all of humanity. That means we're stuck with a choice. Do we bring back everyone's family? Or do we bring back him alone?"

- Explaining to Yu there is a choice between restoring Mika or all of humanity.

Trivia

 * The author, Takaya Kagami, thinks of Guren as "The Unparalleled Ichinose!" while writing him.
 * Guren 「紅蓮」 means "crimson lotus."
 * Ichinose 「一瀬」 means "one rapid."
 * He is one of the first characters designed, along with Mikaela and Yūichirō.
 * The volume covers have humans on odd-numbered volumes and vampires on even-numbered volumes. Guren is the only member of the Japanese army to appear on an even-numbered cover so far, which would appear to be a undeclared hint that he had been working with the vampires all this time.
 * In chapter 14, Kureto promises to give Guren a reward for his efforts in Shinjuku. Takaya Kagami's Q&A revealed that it actually turned out to be chocolate ice cream.
 * In the popularity poll, Guren earned 4th place at 3,307 points. In the 2019 popularity poll, Guren ranked at 4th place with 3,616 votes.
 * There was already a demon inside Guren's heart before he even made a contract with Noya.
 * According to the Manga 8.5 Fanbook:
 * Interests and Likes: [Interests] Yūichirō/Mahiru [Likes] Games/Jazz
 * Favorite food: Curry
 * What he looks for in the opposite sex: Mahiru Hīragi
 * Comments about him:
 * Shinya: "Guren is a pretty shy person. Although he really likes us, he’s not very straightforward about it."
 * Kureto: "That guy works well. He appears to be doing something under cover, but I’m planning to capture him as a hostage for now."
 * He resurrected his deceased friends by using the Seraph of the End experiment using their severed heads and bodies.
 * Guren is the only person who wields two demons at the same time.
 * Guren's greatest desire is him being in the day he met Mahiru in his hometown, with him training swordsmanship, and having a cookout with his friends. In addition, his father would be still alive.