The story is about Takamaru. He attends the Ten Treasures Academy. Like any self-respecting Japanese schoolboy, the boy dreams of seducing some girl. His amorous adventures are perpetually hindered by Shihodo Narika. As it happens, he rents an apartment from her father. One day the boy's pleas were heard and a real beauty, Takamori Haruka, was transferred to the academy, whom Takamaru immediately fell in love with. That same night, he and Narika are pursued by a group of mysterious ninjas. Just when they thought that there is no hope for salvation, Haruka, dressed as a kunoichi (female ninja), appears out of nowhere. Calling Takamaru a "young master", Haruka asks to have sex with her. It turns out that she needs sex to fuel her superpowers, without which she cannot defeat these ninja.