One day, while her husband was away on a business trip, Maya found herself alone at home. To ease her loneliness, she indulged in masturbation. Her lustful moans lured her stepson Jun into secretly watching her, and overwhelmed by uncontrollable desire, he forcefully made his move. Witnessing the scene by chance, her biological son took action—not only to protect his mother, but also to win her back for himself.