Ruka has found a new family through remarriage. She and her husband love each other, but she still struggles to connect with her adult stepson, leaving their relationship awkward and strained. When her husband leaves on a company trip, the two are alone together for the first time. Ruka tries to bring them closer with affectionate physical contact, but her voluptuous mature body and unguarded gestures ignite her adult stepson's long-suppressed desire.