Akira Asai is a human teenage girl with a noticeably curvy build and short, tousled hair that blends black and dark brown hues. Her dark eyes, which sometimes appear amber, have tiny pupils. She typically wears her school uniform: a long-sleeved white shirt, striped tie, grey skirt, and brown loafers, adding a grey blazer in cold weather. For physical education, she changes into a dark track jacket with partially white sleeves, black shorts, and ties her hair in a ponytail. At home, she prefers sleeveless shirts and pajama shorts. Born on May 3, she maintains a disciplined routine, sleeping at 8 PM and rising as early as 4 AM for pre-school walks. Once lively and talkative as a child, she grew increasingly withdrawn due to dissatisfaction with social interactions, a lack of meaningful connections, and an unfulfilling home environment. She exhibits signs of depression, reacts negatively to overly positive statements, and masks alienation with guarded sarcasm and dry wit. Akira is deeply loyal to her childhood friends Kou Yamori and Mahiru Seki, viewing Kou like a younger brother and treasuring their bond. She can become hot-tempered and physically assertive when irritated but supports her friends’ unconventional choices. She harbors strong distrust of vampires, though she accepts their existence when confronted with evidence. She supports Kou’s goal to become a vampire, promising to let him drink her blood after his transformation, and eventually befriends Nazuna Nanakusa despite initial disapproval. When Mahiru becomes involved with a vampire named Kiku Hoshimi, Akira actively intervenes and later mourns his death. Her relationship with Kou evolves as he becomes a half-vampire; she grows somewhat fearful of his personality changes but maintains their close bond. She consistently prioritizes her friends’ well-being, even when it conflicts with her own discomfort.