A serious girl her age, Riena, got into trouble because she couldn't keep up with her classmates' sexual topics and couldn't talk to anyone. One day, I went to my teacher's house on a day off to have my homeroom teacher teach me about sex. However, the teacher is a genuine porn teacher, goes to customs every Sunday, and is trying to get rid of troublesome students who visit his house to go to customs that he has booked in advance, but He was so stubborn that he took advantage of her curiosity and toyed with her body in the process of developing.