Ryouko was masturbating when suddenly her son caught her in the act. Though she continued right there, her son, feeling unsatisfied, boldly made a suggestion: "Let me penetrate your back door." At first, Ryouko refused, saying, "No, anal is... dirty and it hurts..." But as her son inserted a vibrator into her anus, eventually driving his rock-hard penis deep into her ass, intense pain and pleasure intertwined. Screaming in ecstasy, Ryouko was swallowed by waves of pleasure.