Ayaka is happily married to her husband, but she ends up having a physical relationship with her son Kazuya. She knows it's wrong, yet her body reacts involuntarily. As their bond deepens, Ayaka's heart begins to waver. Whenever her husband is away, her desire for Kazuya becomes uncontrollable. The story portrays Ayaka torn between keeping this secret and being overwhelmed by her own emotions.