During the exam season, Hitomi is in charge of her husband's nephew, Hiroshi. When she meets him again after a long time, she can't believe her eyes, as he has grown into a strong young man. Meanwhile, Hiroshi is fascinated by Hitomi, who is just as beautiful as ever. Their relationship, which is as far apart as that of a mother and daughter, begins to go awry when her husband buys an SM magazine. The two are unwittingly drawn into a sensual SM world that they had never known before, and in the afternoon when her husband is not around, they secretly engage in sexual acts, even though they know it is wrong...
