Kim Bongseok is not exactly a "down-to-earth" guy. Born with a condition that causes him to float uncontrollably, Bongseok is forced to hide his power from his peers. But when classmate Jang Heesoo, who is hiding a violent past at her previous school, sees Bongseok floating one day, she promises to keep his secret if he keeps hers. As the two grow closer, Bongseok realizes he has more control over his power than he knew, and that those around him might have some supernatural secrets of their own...