Mother Tomoyo is set to marry her boyfriend. One day, Tomoyo's fiancé invites her son Shunsuke along on a hot springs trip. Though reluctant, Shunsuke cannot refuse and joins them. During this journey, the relationship between them begins to shift. Amidst a mix of warmth and tension in their everyday interactions, Shunsuke starts developing new, forbidden feelings. A poignant story depicting the fragility of family bonds and the turmoil of emerging emotions.