Described as a tomboy with a stubborn streak, she is overprotective of Tsukune, as she is like a "Big Sister" to him, and makes her appearance on the second day of the school festival while searching for Yōkai Academy. Tsukune and his friends attempt to keep her from finding out about the academy's nature and its students, as well as prevent the authorities from discovering she is human. Kyōko manages to enter the yōkai world after she is asked to deliver a mysterious package to someone, while trying to find Tsukune. The envelope contains the Lilith Mirror, which houses a fairy, who claims it grants the owner any wish they desire, but at the cost of their soul.