Miki, a single mother, lives with her son Soshi. Miki works as a caregiver at the home of Takuya, her son's classmate. Takuya lives alone with his grandmother, who is currently abroad. As Miki continues visiting daily, Takuya, entering adolescence, begins developing romantic feelings for her. Unable to restrain himself, he forcefully takes her. Witnessing the incident, Soshi is driven to confront Takuya in a desperate attempt to protect his mother as his own.