Set in an elementary school and centered on a boy named Takuya and a new transfer student named Saeko. 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.
El joven noble Asano decide combatir a Kira, un viejo señor feudal que ha logrado su posición mediante actos injustos y corruptos. Con este fin, Asano se niega a pagar los tributos que Kira le reclama. Al conocer la decisión, Kira pone en marcha un plan para humillarle, empujando a Asano al harakiri (seppuku). Los samuráis que sirvieron a Asano, ahora marginados ronin, prepararán la venganza.