Natsu is a diligent high school girl who is a member of the library committee. One day on her way to school, she is molested and consults with her teacher, Kozuka. In fact, Kozuka was the molester and raped Natsu in the library. Natsu is unable to make a sound and just lets him do what he does to her. From then on, he begins to molest her boldly on trains and in libraries with other students. Eventually, he trains Natsu's body and does it right in front of the person he likes.