Sumi Kurokawa stands at the peak of happiness after accepting her boyfriend's marriage proposal. When he tells her, "I'd like to introduce you to my boss, who's been a great help to me," she feels cherished and honored. However, the man who appears is her senior from college—a man she's always despised and avoided despite his persistent advances. Now in a position of power as her fiancé's superior, he quickly dominates her with his words and actions. When he tells her, "I've always had my eyes on that ass of yours," disgust should overwhelm her—but instead, her body betrays her, climaxing repeatedly. Confused and tormented, Sumi is swept into an uncontrollable whirlpool of conflicting emotions.