Kwon Jung, a stiff and inflexible college student, can’t stand his handsome and popular classmate Kwak Hyun-woo — the very same guy who toyed with and dumped the senior Jung-ha secretly had a crush on. Whenever they meet, they clash like cats and dogs. But one day, after Jung-ha picks up a mysterious necklace, everything between them changes. “It might sound crazy, but… I’m a demon.” Hyun-woo reveals that he’s actually a demon — and that all the magic stored in the necklace has been absorbed by Jung-ha. If he doesn’t get that power back, Jung-ha will die. The only way to return the magic… is through physical contact. With no other choice, Jung-ha ends up living with the demon.