After losing her husband, Chisato lives alone with her son, Yoshio. Lately, she's begun to rediscover her identity as a woman. One day, Yoshio's friend Yamada visits and finds her home alone. When he asks her to play pretend and act as his mother for a day, Chisato agrees to help him. Responding to Yamada's innocent affection, her emotions slowly begin to shift. Before long, their relationship takes a turn into forbidden territory. The passion she had long forgotten awakens once again.