Miiro, a serious girl of her age, was secretly worried because she couldn't keep up with her classmates' sexual topics.One day, she took the plunge and visited her teacher's home on a holiday to have her physical education teacher teach her about sex.However, the teacher is a genuine lustful teacher who goes to the sex industry every Sunday, and at first he tried to turn away Miiro, who visited the teacher's home to go to the sex industry he had reserved, but she was so persistent that she was curious. Taking advantage of her heart, she toyed with her body, which was still in the process of development.