Long ago, demons preyed on humans, feeding their drained souls to their ruler Gwi-Ma. Eventually, three women became demon hunters and used their singing voices to create a magical barrier against demons called the Honmoon. In the present, the K-pop girl group Huntrix are the latest demon-hunting trio. In the demon world five demons form a boy band called the Saja Boys to steal Huntrix's fans and weaken the Honmoon.