Kaoru Ayatsuki is a 60-year-old housewife who has been married for 30 years. Her husband has now retired, leaving him with less time to attend to her needs as he once did. Though he has always been kind and supportive, even remaining sexually active after reaching retirement age, she has recently felt increasingly unfulfilled emotionally. One night, she was shocked to realize she had given in to her desires and slept with her younger son. Since then, her eldest son has also begun pursuing her body. Now, the bonds of family are being tested in a new and forbidden way.