Her father-in-law, widowed and burdened with intense sexual desire, leers at his son's wife, Miyuki, with lustful eyes every day. Miyuki, too, feels unfulfilled in her marriage and struggles with pent-up desire. One afternoon while her husband is away, her father-in-law can no longer suppress his urges and forcefully approaches her. Though Miyuki resists at first, she gradually succumbs to his rough, aggressive advances. From then on, she is subjected daily to intense training—bound tightly, forced into deep throat, tormented with vibrators, and repeatedly creampie fucked. One day, her husband returns home early and catches his wife and father tied up together in the midst of sex. This shocking scene irrevocably changes the family's relationships forever.