During her husband's long business trip, Ai lives peacefully with her son. However, her quiet life changes when her shy son Kazuya invites his classmate Shou over. Ai feels happy seeing her son making friends. Shou, raised in a single-parent household without a mother's affection, begins to develop an intense obsession with Ai. His interest deepens day by day as he gradually closes the distance between them. Seizing a moment of vulnerability, he forcefully pins her down. Her body, long untouched, grows hot and wet, overwhelmed by intense pleasure that pierces straight through her mind. The powerful sensation takes complete control, and she slowly finds herself drawn into the forbidden affair with Shou.