Fifty-year-old mother Yumi is dissatisfied with the monotonous sex she's had with her husband for decades, and while waiting for her son to return home, she relieves her stress through masturbation. However, one day when her son comes home, all her pent-up frustration erupts as she passionately enjoys sex so intensely that she passes out. In that moment of liberation from her mundane routine, she rediscovers the importance of taking care of herself.