A pregnant daughter contacts you urgently, so you rush to her parents' home in Tokyo. Upon arrival, she tells you about some issues going on but also mentions that her stepson, Junya, keeps pestering her. She seems to have called you over as a distraction from his advances. However, things escalate when she reveals that not only does she forbid him from masturbating, but she has even issued an explicit ban on it! Despite this, you can't help but feel sorry for him after hearing his story. One day, while trying to calm him down, you accidentally loosen his restraints. His pent-up sexual desires explode, and he aggressively thrusts his throbbing cock against his stepmother's plump body...

妊娠中の娘から連絡があり、急いで娘夫婦の家に上京してきた友貴。何事かと娘から話を聞くが義息子の純也が所構わず迫ってくるので、抑止する存在として呼ばれたらしい。それだけには留まらず、娘はオナニー禁止令まで出しているというのだ。純也の話も聞き、同情した友貴は手でしてあげると情けを掛けてしまう。1度、栓が緩んだら義息子の性欲はとめどなく溢れ出し、義母の熟れた肉体にパンパンのチ〇ポを激しく打ちつけて…。