Maiko is a 50-year-old mature woman who one day realizes her son is becoming interested in women his own age, stirring deep inner doubts. When her son lashes out at her with harsh words, Maiko can no longer restrain herself and ends up having sex with him. Though aware of the wrongness of her actions, she finds her desire growing uncontrollable. As their excitement intensifies, they begin passionately craving each other, moans escaping their lips, completely overtaken by lustful emotions—ultimately sinking deeply into the forbidden act of incest.