Hina Watarai, 29 years old. A gentle mother raising a 3-year-old son. She moved from the countryside to Tokyo, got married, and gave birth. While she handles housework and cooking perfectly, her relationship with her husband has grown cold, and she is considering divorce. She secretly uses birth control to prevent having more children with her husband. However, she does not use birth control in her relationships with her fuck buddies. A mother's secret that she can absolutely never tell her husband.