Ayumi, a single mother who raised her eldest son and daughter on her own, felt it was finally time to seek happiness for herself now that her daughter, Miki, had married and settled down. However, after a painful breakup, she found herself emotionally shaken and depressed. At that moment, her daughter and son-in-law, who were building a new house, asked to temporarily move in. As she spent time with her son-in-law, Hideki, Ayumi unconsciously felt her suppressed desires awaken, drawn to his quiet charm. Meanwhile, Hideki couldn't ignore his growing attraction to Ayumi's mature, sensual allure, though he struggled with guilt over his forbidden feelings. As their emotions intensified, a secret and passionate relationship began to unfold between them.