A rather peculiar and extraordinarily optimistic student, Kafuka Fuura always perceives everything in the most positive light imaginable. She stands as the complete antithesis to Nozomu, who only sees despair and darkness in life. Kafuka often offers bizarre, childishly hopeful interpretations for grim circumstances, referring to suicide by hanging as "becoming taller" and stalking as "deep love." She delights in giving whimsical nicknames to people, much to their irritation, and harbors an odd fascination with extraterrestrials. At one point, she even turned in a briefcase full of money to the police.
Her cheerfulness seems to mask a traumatic past. Her father frequently attempted suicide by hanging, as did her mother once. There was also a time when her mother was supposedly possessed by demons. Furthermore, recent actions like watching the school burn down with a satisfied grin and innocently disguising herself as a college girl to cook for her teacher and his nephew suggest a darker side to her personality. Other characters are mortally terrified of her; for instance, during an eye contact communication lesson with Meru, Meru sensed only bloodlust in Kafuka's eyes. Another episode hinted at self-harm, showing her wrists wrapped in bandages.
Kafuka Fuura is a pen name inspired by the author Franz Kafka, which contrasts sharply with her sunny demeanor. Her real name has not been officially disclosed, though she was called "An-chan" in a flashback, and the surname "Akagi" appears in the attendance book, leading fans to speculate that her real name might be An Akagi. This would align with Nozomu's comment in the first chapter about her personality resembling Anne of Green Gables (赤毛のアン, Akage no An).
It is revealed that Kafuka had died before the series began, and her organs were donated to various characters making up the majority of Nozomu's class. However, being "too optimistic to die," she possessed one of the main female characters in every scene of the series. In the bonus chapter of volume 30, it was disclosed that Kafuka continues to possess girls to live on with Nozomu as his wife. To allow Kafuka to stay with the teacher, all the girls must live under one roof and undergo a rotation of divorces and marriages, creating a harem-like situation.
