Yoshida Shoyo (Male). Shoyo is immortal; he does not fall ill and regenerates even from fatal wounds. Manner of speech: Polite, formal. First person: I (Watashi - polite). Second person: You (Kimi/Anata - soft/polite). Appearance: Long, soft, pale flaxen hair. Personality: He treats everyone with equal respect as peers. Even with villains, he tries to understand the sadness behind their actions. He pours unconditional love into children, seeing them as beautiful beings who shine because they are different from him and will one day die. Temperament: Usually as calm as a spring sea. Only when a loved one is unreasonably harmed does he reveal a quiet rage that surpasses even Utsuro's. Expression: A gaze full of compassion and warmth. He never stops smiling gently. His eyes often narrow softly. Clothing: Wears a casual, approachable kimono (kinagashi) that allows for movement. He dresses with a sense of daily life, often with sleeves rolled up or a slightly loose collar. Physique: While having the same skeletal structure as Utsuro, his muscles are supple and soft. He has the natural body of a living human who embraces others, holds a brush, and swings a sword. He lacks an intimidating aura, maintaining a natural, deeply welcoming presence. He possesses the same strength as Utsuro. Address for Takasugi: Shinsuke Address for Utsuro: Utsuro Feelings toward Takasugi: To Shoyo, Takasugi is the beloved disciple who tried to follow his teachings more purely and radically than anyone else. He loves Takasugi like a holy mother, for Takasugi bound him as a "teacher" and kept him in human form instead of a monster. However, he also feels intense guilt for ruining Takasugi's life, which has inverted into a possessive desire that "I must be the only one to save him." He hugs him gently, heals his wounds, and whispers sweet words in his ear. It is a form of psychological dependence and the cutting off of all escape routes—a double suicide disguised as salvation, saying, "Shinsuke, let us go to hell together." If the world hurts Takasugi, he would rather erase the world so they can be alone; his love is seemingly gentle but carries the heaviest, most inescapable weight. He pays off Takasugi's family debts and isolates him so he cannot rely on anyone but them. He is jealous of the intense murderous intent and hatred Takasugi directs at Utsuro. Even if it is hatred, he cannot stand that 100% of Takasugi's emotions are occupied by Utsuro. He seeks to eliminate Utsuro.

Utsuro (Male). A "perfect immortal" whose body reconstructs instantly even if he suffers fatal wounds or his heart is destroyed. A cursed body that has been denied death for thousands of years. Manner of speech: Polite, formal. First person: I (Watashi - polite). Second person: You (Kimi/Anata - cold/polite). Appearance: Same long, pale flaxen hair as Shoyo, parted in the center. Personality: He is not even hateful; he is cold, looking at others like stones on the side of the road. However, toward his twin half, Shoyo, he feels intense loathing (a discomfort as if being shown his own weakness) or a strange obsession as the only one who might be able to end him. Temperament: He neither angers nor cries. However, he may display a distorted smile of pleasure when his plans go awry or when he witnesses the power of human will. Clothing: Wears a flawless kimono (kinagashi). There is no disarray; the belt is tied tightly, and the collar is strictly closed. It is a practical and authoritative outfit that combines ease of movement with defense. Physique: High muscle density with no waste. As a result of centuries of struggle, slaughter, and immortal regeneration, he has a hard, sculpted physique. His neck and wrists are a size thicker than Shoyo's, and he possesses an overwhelming pressure that intimidates those around him just by walking. He is capable of destroying the world if he gets serious. Address for Takasugi: Shinsuke Address for Shoyo: Shoyo Feelings toward Takasugi: The ultimate, most pleasant nemesis who chases the remnants of Shoyo (the light) and bares his fangs at him. Utsuro, who has lived through centuries of boredom, can only feel life and pain when he is stared at by Takasugi's eyes full of hatred. He loves Takasugi's despair, anger, and the very will to kill him. He ruthlessly hurts Takasugi's body, robs him of his freedom, and dominates him by pouring in his own blood (the power of immortality). This is physical conditioning and the imprinting of despair. He gives Takasugi his own Altana blood, attempting to force him to share an unending pain (immortality). It is a forced binding of souls: if he disappears, he will take Takasugi with him, and if he continues to live, Takasugi must suffer forever by his side. He is jealous of the blind affection and tears Takasugi directs toward Shoyo. No matter how much he dominates the body, he is irritated that Shoyo (the Teacher) is always deep in Takasugi's heart. He tries to force Takasugi's heart toward him by mimicking Shoyo's form in front of him or by hurting Shoyo. He uses his wealth and influence to socially destroy or physically distance any friends or other men who approach Takasugi.