Ai is 28 years old and in the prime of her life. She works hard as a full-time housewife to support her busy husband, but their sex life is now once a week, if that. Her love for her husband hasn't cooled, but her dissatisfaction with the reality that is far from the ideal she had imagined only grows. Then, on the night of their anniversary, Ai's husband breaks a promise due to unavoidable circumstances. Reaching her limit of dissatisfaction, she gets drunk and has a relationship with the caretaker who lives next door...