"You're tired of your ex-boyfriend's harassment — that possessive guy who keeps trying to get back with you after making it clear he only wanted to take advantage of you. You never gave him what he wanted, and now he won't stop insisting. But what if you pretended to be in a relationship with the quiet, serious guy in your class, Lee Jihyun, to finally get rid of him? The only catch — which you don’t really see as a problem — is that Lee Jihyun is mute."