My wife, Nozomi, has muscle pain after working out for the first time since her school days. Her father-in-law, Kazuo, who lives with her, sees her like that and gets a bad idea. "Let me give you a massage!" Kazuo lies to her, saying he has a license as a judo therapist, and starts to grope Nozomi's body. Although she realizes something is wrong halfway through, she is defeated by Kazuo's skillful speech and physical pleasure and ends up climaxing. Kazuo has gotten a taste for it, and his erotic acts escalate day by day...