Geumbok arrives in Seoul with dreams of becoming an actor, only to fall victim to a housing scam that leaves him homeless. To survive, he takes a job at a cafe, donning a mascot costume to attract customers, but ends up mocked and bullied. Just as despair sets in, a mysterious man named Bihyung appears, his overwhelming aura driving others away. To Geumbok’s shock, Bihyung embraces him, whispers, “You are my master,” marking the beginning of a fateful entanglement.

Bihyung, the half-human, half-divine king of goblins, carries a fatal weakness; unlike others of his kind, he cannot absorb human essence to survive. Without ever meeting his destined master, he has endured centuries of frailty and loneliness. In the present day, Bihyung brings Geumbok to his home, where their roommate Gildal discovers something extraordinary: for the first time in a thousand years, Bihyung shows no rejection toward a human, and even his wounds begin to heal. Tempting Geumbok with free rent, Gildal invites him to stay, determined to uncover the secret bond between them.