Emiko lives with her husband and son in a quiet, rural village surrounded by nature. Her days are peaceful and ordinary, but she gradually grows dissatisfied as her husband consistently neglects her sexually, often returning home late. One evening, while preparing dinner, her husband's close friend happens to pass by her house. By chance, he discovers Emiko masturbating and immediately forces himself on her, climaxing inside her right there. Unbeknownst to them, her son, who was coincidentally walking through the hallway, witnesses the entire act. Days later, when her son confronts her about what he saw, Emiko begins a deeper sexual relationship with her husband's friend while repeatedly engaging in sexual acts with her own son to satisfy his desires. Her once-normal life takes a dark and twisted turn.