Set in an elementary school and centered on a boy named Takuya and a new transfer student named Saeko (Maeda Ai plays Takuya's younger sister). Takuya's classmates think that Saeko has been possessed by Hanako, the ghost that lives in the bathroom. The rumor is especially encouraged by a girl who has a crush on Takuya and is jealous since Takuya likes Saeko.