Yukie, a married woman, goes on a hot spring trip with her housewife friends. Having had an affair before, she constantly complains about her husband, souring the mood around her. The story takes a sharp turn when she approaches a gentle, pure-hearted herbivore man she meets by a vending machine. Coaxed by his friends, the situation quickly spirals out of control. Dragged into the mud, her resistance becomes meaningless as her defenseless body is pinned down. Fearless and reckless, the men continue to treat her like a toy. One after another, they rape her in the room and the outdoor bath, relentlessly creampieing her. Her body and mind are pulled deeper and deeper into a swamp of pleasure.