Her husband is consumed by work and shows no interest in intimacy, leaving their marriage strained and emotionally distant. Yumi finds solace only in spending time alone in the bathroom. One day, her husband brings home his junior colleague, Masaya, from an izakaya. At that moment, Yumi is bathing. Masaya accidentally soils his suit and ends up meeting her. The drunken husband quickly falls asleep, leaving the two alone in an awkward, tense atmosphere. Yet, as their eyes meet in the bathroom, an uncontrollable excitement stirs between them, sparking a forbidden passion and a new, illicit relationship.