Stepmother Ruri lives with her husband's stepson, Yoshio, while her husband is away on a work assignment. Recently, she's become aware of Yoshio's lingering glances and finds herself confused by her growing awareness of him as a man. Meanwhile, Yoshio fantasizes about Ruri being taken by his classmates, tormented by the lewd images in his mind. Their forbidden desires converge until he pours out his feelings, pressing himself against her gentle motherly warmth and confessing his son's longing.