ONA
Description
Raian Kure is a fighter and assassin who belongs to the Kure Clan, a family that has spent roughly thirteen hundred years, since the Asuka period, refining itself through selective breeding and the adoption of outside martial arts until it became a bloodline specialized for battle. As a member of the clan, Raian was raised within its martial traditions and trained in assassination techniques. He is regarded as the black sheep of the clan, and his relative Kure Karura characterizes him as a figure whose psychopathic and ruthless attitude sets him apart from the rest of his family. He has also earned the epithet the Devil, a name that reflects both the fear he inspires and the unrestrained violence of his fighting style.

In personality, Raian is aggressive, blunt, and highly combative. He tends to be far more offensive than other participants in the Kengan matches and shows little interest in the formalities or stakes surrounding them, stating that he does not care about winning or losing as long as he has an opponent. During the Kengan Annihilation Tournament, he expressed a desire to defeat or kill every competitor in order to prove that he was the strongest. Despite his cruel and volatile behavior, he carries a deep loyalty to his family and a respect for its traditions, and much of his sense of identity is tied to asserting his superiority through combat.

His motivations are driven by an obsession with strength and fighting. He wants to test himself against the most powerful opponents and dominate them through sheer physical force, and he sometimes treats battles as opportunities for slaughter rather than sport. This aggressive mindset, combined with his refusal to show restraint, makes him one of the most dangerous and unpredictable fighters in the story.

In the events of the series, Raian enters the Kengan Annihilation Tournament as the affiliated fighter of Under Mount, Inc., and is one of three assassins among the competitors. His matches are marked by brutal displays of raw power, and he eventually clashes with Tokita Ohma in an extremely violent and decisive battle that ends in Raian's defeat. After the tournament he is noted to have gone missing for a period of time. In later events, he returns as one of the thirteen representatives chosen for the Kengan side in the Kengan versus Purgatory tournament, where he fights Alan Wu and kills him by tearing him in half.

His most significant relationship is his rivalry with Tokita Ohma. Their fight is a defining moment for his character, as it forces him to face an opponent who can match his natural abilities and reveals the shortcomings of fighting on brutality alone. His ties to the Kure Clan remain central throughout, as does a strained connection to other clan members such as Karura, who disapproves of his behavior. He is also known for treating killing as an ordinary part of combat, a stance that distinguishes him from more restrained fighters.

His defeat by Ohma serves as a turning point, after which he disappears from public view for a time. When he reappears for the Kengan versus Purgatory tournament, he remains just as violent, but he now operates within the larger structure of the Kengan matches, taking on the role of a recognized elite fighter who can be selected to represent his side.

In terms of abilities, Raian possesses superhuman physical condition as a product of the Kure bloodline, including an unusually high tolerance for pain owing to elevated endorphin levels. His fighting style combines Kure Clan martial arts with assassination techniques, many of which focus on disabling strikes to vulnerable areas such as the eyes, throat, neck, and abdomen; examples include Mumyo, a finger swipe across the eyes that causes temporary blindness, Butsugari, an elbow strike to the throat, and Shishigami, a two-handed grip on the neck that dislocates the bones. His most notable trait is his mastery of the Kure Clan secret technique of Release, which removes the brain's natural safety limiters that normally restrict human strength to a small fraction of its potential. Through generations of selective breeding, the Kure Clan developed bodies capable of withstanding that strain, and Raian can maintain a Release rate of one hundred percent, a level achieved by only an extremely small number of people in the clan's long history. This ability is what led to his being called the Demon. He is also physically strong enough to wield Ootakemaru, a twenty-kilogram nodachi whose weight is distributed unevenly and which requires the user to perceive the flow of force and master the blade's center of gravity; Raian uses it in a self-created two-sword style, holding the scabbard in his left hand and the blade in his right.
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