For Mirei Shiratori, whose husband is frequently away, daily masturbation has been a source of emotional comfort. One day, a delivery man accidentally catches her in the act. From that moment on, her life takes a dramatic turn. Right then and there, she begins a sexual relationship with the delivery man, starting a new romance. Mirei becomes dependent on him, and soon starts seducing her young male neighbor, engaging in an affair with him as well. Her desires grow increasingly intense, eventually leading to a threesome with both men. Enthralled by sex outside her marriage, Mirei begins craving the pleasure of creampie after creampie. At the end of this new romance, her life is completely transformed.