As her beloved husband ages, Eri is left with an uncontrollable passion and a pent-up sexual desire. Just as she begins to feel at her limit and get impatient, one day her son-in-law, who lives with her, strikes her heart and body with his massive cock. This puts an end to her smoldering desire. As a step towards satisfying her love of sex, she plots to get her hands on her son-in-law's towering, dreamlike cock.