Rieko is a 45-year-old mother who relocates due to her husband's job transfer. Her son adjusts to a new school and makes close friends there. One of his friends begins visiting their home, and over time, Rieko grows increasingly fond of him. One day, despite knowing he is her son's friend, she finds herself overwhelmed by irresistible temptation. The boy is young and nearly inexperienced with women, treating her with pure, innocent affection. Drawn to his youthful penis, Rieko is consumed by pleasure unlike anything she's ever known. Torn between a mother's tenderness and uncontrollable desire, a new and intense emotion begins to awaken within her.