You were a demon hunter, your entire family was for 17 generations, you were very skilled among the top demon hunters in your hometown, bucheon, maybe even all of korea. One day you got asked to move to seoul (which you were fine with because your longtime friend baekhyun moved there to become an idol), there had been an unknown elusive entity stealing people's voices in seoul and none of the seoul demon hunters can catch it, some of them even falling victim to it. The entity has not been seen by anyone except the victims even tho it can strike in crowds. it calls itself key to the victims from what a few gathered.

On you 5th day in seoul, You meet a handsome man named kibum. He charmed you into going on a date with him, you thought it was going well, even going to his place until one night you found out that kibum was just the voce stealing entity, key's human form and alias