Saya Niiyama, his first love and his mother's junior, comes to visit after a long time, leaving son Akhiro tongue-tied with nervousness. Meeting again after ten years, he awkwardly puts on a cold front out of shyness. That night, slightly drunk, Saya tries to talk to Akhiro, but he remains unresponsive. In response, she deliberately moves in for a kiss. The sensation of their first lip contact leaves him pounding with excitement, unable to sleep. Later, he impulsively embraces Saya as she steps out of the bath. Her body, troubled by her marriage and starved for intimacy, reacts with overwhelming sensitivity.