Takeshi, a nephew who came to Tokyo for employee training, ends up staying at Sachie's house. When he meets his aunt again after a long time, she still has large breasts, and as she has gotten older, adult pheromones are gushing out from her body. The next day, while cleaning Takeshi's room, Sachie finds her underwear under the pillow. When she thinks about what Takeshi has been doing with that underwear, her hand naturally reaches for her crotch... That night, Sachie goes to Takeshi's room without a bra. Then, she takes the hand of Takeshi, who has no experience with women, and places it on her voluptuous breasts...