Momo is married to her current husband and has a carefree life, but there are certain things that she is not entirely satisfied with. One day, Momo attends a class reunion and meets Sato, her first love. Although they loved each other in the past, it was Sato who made Momo a woman, not her husband, yet neither of them expresses their feelings. This time, Sato doesn't want to regret anymore; he takes the initiative to confess to Momo, something he hasn't dared to say for years. They have a pleasant conversation, and Momo drinks a bit too much, quickly becoming intoxicated, so Sato has to take her to a hotel to rest. Looking at his beautiful and seductive ex-lover in front of him, Sato uses her drunkenness as an excuse to once again get close to her. Although Momo protests with her words, her body responds to every touch from him. She also remembers the pleasure that Sato brought her, something her current husband cannot provide. From then on, Momo continuously lies to her husband to meet Sato, and her husband, trusting her completely, never suspects anything...