Chizuru Iwasaki is a 52-year-old housewife living with her two sons, her eldest and second son. A few years ago, she began an affair with her eldest son, who recently returned home after getting divorced. Feeling lonely from the divorce, her eldest son grew emotionally attached to her, causing the relationship between her and her sons to evolve into a new form. The second son is completely unaware of this situation, and as the three spend time together, a story unfolds filled with complex emotions and the bonds of family.