After losing touch when they both married, a man contacts his childhood friend Yu while visiting Tokyo on business. They reunite and reminisce, but the bar closes early, so she eagerly suggests buying alcohol and continuing in his business hotel. They cross the line and discover astonishing sexual chemistry despite their initial shyness. Deep kissing, bathing together, and more than a decade of pent-up feelings make it impossible to stop; throughout his three-day trip, they meet secretly for repeated adulterous sex and creampies.