It has been five years since Misao (Kawakami) married Miyuki's (Kurata) older brother. The sisters-in-law, who taught at the same school, were as close as real sisters. ...However, the relationship between the two begins to become distorted due to the sexual tendencies of one of his students. The student's name is Ryo Nishiki, and he usually plays an ordinary high school boy. However, when the sadistic desire that grew within him goes out of control, the day of the young female teacher sisters...