Hyo-Woon is a kid who one day meets the cheerful Seon-Heung at the rural school where he was transferred after a certain event took place. Here, the two of them will experience the beginning of an immature love, fitting for the school setting they're in. However, one day, Seon-Heung suddenly disappears like smoke, bringing an end to their beautiful, young love that was beginning to bloom. Ten years later, Seon-Heung reunites with Hyo-Woon during a work meeting. Unexpectedly, rather than treating her coldly or feeling betrayed, Hyo-Woon proposes a contract to her. "Ten million KRW a night. Have you thought about it?"