Rikka, an adult college student, misses the last train after a shift at her new part-time job and heads to the nearby home of her male childhood friend. After her bath, she appears barefaced for the first time, wearing his sister’s loungewear that reveals her now-full breasts and flashes her panties. His restraint disappears. More than a decade of mutual feelings finally erupts into affectionate sex and repeated orgasms. They bathe together for the first time since childhood, fuck again in the morning, and spend the entire night giving in to their uncontrollable desire.