When nude pictures of girls turn up on the school's noticeboard, everyone suspects the class outcast, Kenji. Only one girl, Atsuko, defends Kenji. He tells her if she REALLY wants to support him, she'll let him fuck her. And that shit actually works.
This dude Yoshiyuki loves to work out. He also loves sex, cause he's not dead. Now that he's a teacher at an all-girls school, he gets to combine his two favorite things. He decides to give his struggling students some private tuition, AKA, his dick - cause that certainly won't be hard to grasp.