Serious girl Kotone-chan, who has always been, cannot keep up with the sexual topics among her classmates and secretly worries. One day, she decides to visit her physical education teacher's home on a holiday to ask for advice on sexual matters. However, the teacher is a genuine lecher who visits a brothel every week. Initially, he intended to get rid of Kotone-chan, who came to his home to go to the brothel, by exploiting her worries, gradually playing with her body. Kotone-chan, too, takes the teacher's words seriously and gradually becomes dominated in body and soul...
