One day after school, Kaede, the student council president, and Hayato, the secretary, are summoned to the student council room by Kaede's twin sister, Suzu. Kaede is curious about a mysterious box on the desk, and when she puts her hand in it, her hands are restrained... On the day of the cultural festival, Hayato's class decides to have a maid cafe, and the girls dressed in maid uniforms are very active. Of course, his classmate Kaede is no exception, dressed as a maid and serving customers. Then, for some reason, Suzu, who had come to the cafe dressed as a maid, offers him a mysterious switch. Hayato turns on the switch to try it out and Kaede suddenly begins to writhe in agony. It seems that the switch that Hayato pushed is connected to a rotor that is inserted into Kaede...