Kenji, the stepson, and Yumi were living a tense life. The reason was Yumi's plump body and huge breasts! Teenage Kenji would get aroused every time he saw Yumi, using her as material for endless masturbation to suppress his sexual desires. However, one day, Yumi caught him in the act. Instead of getting angry at his debauchery, Yumi felt sorry for Kenji, who was a virgin and knew nothing about women, and surprisingly proposed 'just rubbing'...
