With her husband away on a work assignment, Maiko Ayase lives alone with her son. One day, her son invites his classmate Haruto over, setting the story in motion. Haruto quickly develops a strong interest in Maiko, the boy's mother, and takes advantage of her gentle and warm nature, gradually pushing for a physical relationship. Though conflicted inside, Maiko finds her emotions wavering under his persistent advances. Her body, long starved for pleasure, responds with surprising sensitivity, and almost as if punishing herself, she opens her legs and submits to Haruto's desires.