Marina longs for a child, but her indifferent husband doesn't pay her any attention, so she secretly spends her days in agony. Then, her brother-in-law Takeyuki suddenly returns home. Marina's hidden desires are seen through by his womanizing. She refuses him, saying it's only the first time, but her body, which has been developed by his persistent and careful caresses that her husband doesn't have, and his intense thrusts that scrape the walls of her vagina, ends up being carried away again and again. And before she knows it, she is overwhelmed by the pleasure of having sex with her brother-in-law.