Ai Kamiyo is a first-year high school student who becomes the second tutoring pupil of Keitaro Gentoga. She has a gyaru fashion sense, often seen in colorful attire and heavy makeup, with long blonde hair. Her most distinctive feature is the star-shaped pattern in her eyes, which is not a cosmetic choice but a physical stigma indicating that she is claimed by a god. This marking is a visible sign that she has been chosen as a yorishiro, a vessel bound to a divine entity.

Her personality is openly joyful, friendly, and exuberant, with a noted craving for sugar. Despite the constant misfortune that plagues her life due to her spiritual constitution, she tries to maintain a cheerful attitude. However, beneath this bright exterior lies a deep-seated trauma and a fatalistic acceptance of her grim fate. The source of her suffering is a generational curse on the Kamiyo family. An ancestor’s mistake resulted in the family being cursed to become playthings for a particular god, who claims a member when they reach the age of twenty. Ai is the current chosen one, destined to be taken by this god in four years.

Her spiritual nature attracts evil spirits, causing a cycle of misfortune that often harms those around her rather than herself. The god attached to her emits a powerful energy that lures malevolent ghosts, but it also chases away these spirits to protect its property. This dynamic led to the tragic death of her older brother, who was killed by falling debris while protecting her. Ai initially believed her brother’s spirit was haunting her, which drove her to seek help from Keitaro. In the story, she serves as a key figure who raises the stakes of the supernatural conflict, moving from ordinary evil spirits to a direct confrontation with a god. She possesses no active spiritual abilities to defend herself, making her a protected individual and a catalyst for the group to develop new strategies.

Her most significant relationship is with Keitaro, her tutor, who sees his former self in her despair and refuses to abandon a student in trouble. She forms a strong bond with Yayoi Hozuki, whom she affectionately calls “little sensei.” Yayoi takes a leading role in devising plans to free Ai from her fate. Throughout her development, Ai transitions from passive despair to cautious hope, gaining companions who actively fight on her behalf. A terrifying nightmare in which she relives the fate of previous women from her family solidifies her resolve to escape her destiny. Her only real power is as a beacon that attracts spirits, forcing the other characters to grow stronger and confront divine-level horrors to save her.