Yūichirō Hyakuya

"*I... I don't care what people call me. Call me a demon. Call me a monster. Whatever. It's just... If I can keep my family safe... If I can protect the people who took in someone like me, I'll be happy... Everyone here is my family.*"

—Yūichirō to his squad[src]
**Yūichirō Hyakuya** (百夜 優一郎 *Hyakuya Yūichirō***?**), birth name **Yūichirō Amane** (天音 優一郎 *Amane Yūichirō***?**), is the main protagonist of the *Seraph of the End: Vampire Reign* series. He is a member of the Japanese Imperial Demon Army as well as Shinoa Hīragi's squad in the Moon Demon Company. He, along with Mikaela Hyakuya and a few others, possesses the "seraph" gene, which is relevant to the forbidden taboo and the focal point of the story, "Seraph of the End."

He also appears in prequel materials *Seraph of the End: Guren Ichinose: Catastrophe at Sixteen* and *Seraph of the End: The Story of Vampire Michaela*.

## Personality

### Human

Up until his teenage years, Yu started off as moody and antisocial due to the tragedies during his childhood . As a young child, he saw himself as a demon that no one would love, yet he still held out hope of finding something good in this world. At first, Yu wanted nothing to do with Mika and the other Hyakuya orphans and even challenged Mika to a fight.

Shortly after though, when Mika puts Yu in charge of watching over the kids alongside him and Akane, Yu took on the role of the aloof, yet kindhearted older brother. After losing them, Yu reverted back to being a moody antisocial rebel with a thirst for revenge against the vampires that killed his family for another four years.

Eventually, when Yu opens himself up and becomes a hot-blooded youth with a kind heart. This becomes apparent when his fearless but somewhat reckless actions are shown when he is attacked by a Horseman, ignoring orders. It's made clear that this wasn't the first time. Yu is often called an idiot by those who know him. He is a very narrow-minded person, whose only goal is to annihilate all vampires because of what they did to his "family." He swore to exterminate all vampires for killing his family, especially Mika. Yu will take on any type of challenge in order to accomplish his goal.

Despite this, he has a soft spot, worrying more about his friends first than his goals. (Ferid Bathory considers this attitude to be "cute"). As a result, Yu empathizes with others who put their family first, as seen when a civilian girl gave his squad false information because vampires are holding her family hostage. After learning why she deceived them, he tells the girl that she did the right thing to save her family. He feels guilty for abandoning Mika and has nightmares about Mika's death for four years until he becomes friends with Shinoa and Yoichi. After learning Mika is alive, Yu's personality changes in response and he grows more mature, as noted by Shinoa. He puts more effort into being patient and calm and making friends, and immediately amends his worldview to include Mika even though he is a vampire. His dream of wiping out vampires takes second place to reclaim Mika. Regardless, even though his best friend is now a vampire, Yu still slaughters them without mercy or hesitation. After Shinjuku, he becomes closer to his squad members and makes Guren promise to help him take Mika back under the promise that Mika will be useful to him, as he comes from the same orphanage as Yu. Additionally, friendship and bonds become more important to him, as shown in a mental battle against Asuramaru, to gain more power or else lose his body, he calls Asuramaru his friend and convinces Asuramaru to yield to him.

Rather than revenge, his primary goal changes to protecting his new "family," in order to avoid a repeat of past events. In Nagoya, he surprises Narumi's squad by memorizing all of their names and promising to protect them.

Similarly to how vampires do not bother to remember human faces and only think of them as "humans" or "livestock," Yu only sees vampires as "vampires" or "bloodsuckers" without bothering to remember their names or faces. He does not even recall the name of his vampire target in Nagoya. The only exception to this rule is Mikaela Hyakuya, who he still greatly cares for, and as Ferid Bathory was the one who murdered his fellow orphanages, Yu still cleanly remembers his resentment at Ferid and has been seen to rage when they meet again.

Aside from this, Yu shows to have a somewhat weird sense of humor, as shown when he teased Shinoa for her height.

1,000 years ago he was in good terms with Ashera Tepes and been with Sika Madu for a long time even obeying his orders, despite being used by Sika Madu all along.

In the Dark Ages of Greece, he expresses curiosity over minor or major things such as wanting to see the "Mikaela" corpse, even when very young his personality is similarity to the present one. According to Noya, that even one or more Yu's is killed, Sika Madu would just create dozens of him, upon witnessing the current Yu in the present time Noya is surprised to see a fully grown Yu, wondering if Sika Madu succeeded in finishing the human creations.

## Powers and Abilities

### Natural Abilities

Yūichirō is an excellent swordsman, being trained by Guren himself. He is capable of easily taking down Horsemen with both an enchanted gear and Cursed Gear blades, and has proven to effectively fight and slay common vampires. Yet another testament of his skills is that with just a regular blade, he was able to go up against Shinoa using Shikama Doji, which earned him her praise. Along with that, later he can hold his own in a sword-fight with Guren, although not enough to actually match him equally as Guren was holding back due to it only being a training exercise. Yu was easily defeated by Kureto, a swordsman who was, although only by a slight margin, inferior to Guren in terms of skill. Nevertheless, he earned praise from Aoi Sangū for his sword skills, pressuring her when she blocked his attempt on Kureto's life.

He is also a "Seraph of the End" hybrid with 1/10th of him being not human due to him and his old family being experimented on by the Hyakuya Sect. After he overdoses on the curse supplement to save Guren from Crowley, his non-human part increases.

Upon synchronizing with his Demon his own strength has skyrocketed, although he has yet to control it with his Demon as his own mind went fuzzy and is unstable, but he has demonstrated new techniques.

### Equipment

#### Enchanted Gear

Mass-produced cursed gear, these demon weapons are much weaker, usually of the yaksha or myo-o series, as they increase a regular human's strength by three to four times. Yu wielded one in the form of a katana, and was able to use this gear to easily slay a horsemen and hold his own against the escaped vampire, Noin Teta.

#### Cursed Gear

* Asura-Kannon

* **Asuramaru** (阿修羅丸 *Ashūramaru***?**, lit. "Perfect Asura"): Asuramaru is a possession-type demon weapon of the Black Demon Series, where he takes the form of black katana with a green edge. Whilst in use, the blade develops a thick green aura. Like Mahiru Hīragi, he can call upon Asuramaru to fully use its power to attack opponents.
	+ **Asura-Kannon**: A special technique using Asuramaru that materializes dozens of floating swords.
		- **Asura-Kannon: Thousand Blades**: An advanced type of Asura-Kannon, where a warped space is formed and expand around Asuramaru, which thousands of swords materialize and surface from the warped space with a homing effect at the target.
			* **Asura-Kannon: Ten-Thousand Blades: Knot of Fate**: When used the original warped space range widens, able to cover an entire building, and millions of thousands swords surface from the warped space which materializes with a homing effect at the target. It has enough destructive force to shatter the surrounding area in the warped space.

### Experimentation

* **Cursed Gear Stimulants**: Like other soldiers in the JIDA, Yu takes a supplement to increase his synchronicity with his demon to 150% for 15 minutes. After that time is up, this synchronicity drops to zero. There are numerous unpleasant side-effects including ones internal organs exploding, and officers only resort to this as necessary.

* Incomplete Seraph

* **Seraph of the End**: By swallowing a special tablet produced by Guren, Yu can lose his mind and undergo a painful transformation. Although extremely powerful, he goes berserk and attempts to kill any human nearby. Guren causes this transformation to end by making Shinoa hug Yu. The transformation ceases, and puts Yu into a coma for a week. It takes five days for the drug to get out of Yu's system, and even after that, he feels tired. Yu has no recollection of the events that occur while he is transformed. Later he would be able to control his own Seraph on his own.

By using the golden trumpet within his consciousness, Yu undergoes a drastic transformation. As a completely awakened Seraph, he is the Second Trumpet referred to as the "King of Salt" (塩の王 *Shio no ō***?**). His main power consists of turning every living being into pillars of salt. Additionally, he can also create a spear made of salt that can block Abaddon's destruction ray. He later has full control of his Seraph state.

* **Anime**: He attacks both vampires and humans without discrimination while he only wants to kill humans in the anime and orders vampires like Mika to get out of his way. Additionally, his power is demonstrated more in the anime when he swings his sword and creates a plume of black energy the size of a tall building with a ring of light around its base.