Maki, who lives with her daughter and son-in-law, is a serious person by nature and only knows normal sex. But one day, she finds out that her daughter-in-law, Tetsuya, who is having a sexless marriage with her daughter, has been secretly calling for a nipple teasing delivery health service... She can't help but feel a throbbing in her body, and she teases his nipples, saying that it will help their relationship. Maki can no longer contain her excitement as Tetsuya twitches and reacts in a funny way, and when her daughter isn't looking, she starts teasing his nipples wherever she can...