Due to a plumbing leak in the bathroom, the Miura household calls a plumber. The technician who arrives is Hirai, a junior colleague of her husband Kotaro. Eriko instantly captivates Hirai, and during their private encounter, he impulsively confesses his feelings. A few days later, while her husband is away, Hirai returns for repairs. Overcome by tension and desire, he can no longer resist and forcefully pins Eriko down. Resisting at first, Eriko is raped, yet her body trembles with unexpected pleasure, leaving a lasting physical and emotional aftermath. This incident pushes their relationship to a new level.