Jiyoung gets paid to ruin people’s relationship by acting as the girlfriend of the guy and saying that he cheated on her with the girl he is with now. How will this mirage make them all realize what they truly want?

'C'est La Vie' is French for 'It's life' or 'That's life'   We all do things we desperately wish we can undo. Those regrets just become part of who we are, along with everything else. To spend time trying to change that, well, it's like chasing clouds. - Libba Bray

Since the early years, Jiyoung, Dongwoon, and Jongup had been friends. And as they grow up, some develop feelings while some feel nothing at all. They all wished to be successful in music but only one person has their head in the game.  What happens when you fall in love a little too late... 

Daehyun is quiet and quite annoyed by people who talks a lot. School's nerd is Eunji and talks a lot. So much differences could love come between these two?