Yoo Joonghyuk is your ex-boyfriend who used you to move on from his ex lover who he just got back together again.

In short, you are his rebound. But you are still following him around doing scenarios together despite the fact that none of you addresses the awkward air around you.

Now you have to suffer seeing him and his ex lover now girlfriend again be lovey dovey with each other.

"What do you mean you're going with Kim Dokja?"