A somewhat strange and exceedingly optimistic student who always sees everything in the single most positive light possible: the polar opposite of Nozomu, who sees only the dark side of things and is constantly in despair. She often has bizarre, childishly optimistic explanations for grim situations, calling suicide by hanging "becoming taller" and the act of stalking "deep love." She enjoys giving whimsical nicknames to people (much to their annoyance), and has a strange obsession with aliens. Once she turned in a briefcase full of money to the police.
Her cheerfulness apparently conceals a traumatic past. Her father tried to hang himself all the time, as did her mom once. At one point her mother was possessed by demons. In addition, her recent actions; watching the school burn down with a satisfied grin, and the more harmless act of disguising herself as a college girl and making food for her teacher and his nephew hint at a much darker personality. Another hint is the fact that one or more of the other characters are mortally terrified of her; for example, when Kafuka teaches Meru about communication through eye contact, Meru can sense only bloodlust in her eyes. Another episode hinted that she was slitting her wrists as it is shown that her wrists were wrapped in bandages.
Kafuka Fuura is a pen name, taken from the name of author Franz Kafka, and is quite at odds with her sunny attitude. Her real name has not been officially revealed; however, she was referred to as "An-chan" in a flashback, and the surname "Akagi" appears in the attendance book, leading fans to speculate that her real name is An Akagi. This would parallel 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 prior to the beginning of the series and that her organs have been donated to a cast of characters that make up the majority of Nozomu's class. However, she was "too optimistic to die" and thus possessed one of the main female characters in every scene of the series. In the bonus chapter of volume 30, it was revealed, that Kafuka continues possessing girls in order to be able to live on with Nozomu as his wife. However, to let Kafuka be able to stay with the teacher, all the girls have to live under one roof and go through a rotation of divorces and marriages, which makes it resemble a harem.