Married for 25 years and celebrating their silver anniversary, Nami Okuchi lives with her 24-year-old daughter, 19-year-old son, and 57-year-old husband. She hasn't had sex with her husband in over 15 years, and since her 40s, his stamina has declined, leaving their intimate life nearly nonexistent. With pent-up desires building inside her, she turns to online dating and meets a younger man. Initially planning for just a one-time encounter, she's overwhelmed by his incredible sexual performance and quickly becomes addicted. Before she knows it, she's emotionally and physically devoted to him, pouring everything into the relationship. Though consumed by guilt and shame, she can't bring herself to stop.