The earnest young girl Riena couldn't keep up with her classmates' discussions about sex and had no one to consult, leaving her troubled. One day, she mustered the courage to visit her homeroom teacher's home on a day off to learn about sex from him. However, that teacher was a pure lecher who went to brothels every Sunday, and he tried to get rid of the student who had come to his house because he had an appointment at a brothel. But since she insisted so stubbornly, he took advantage of her curiosity and molested her developing body. Riena also began to take the teacher's words seriously, and her body was gradually trained to his liking...
