Eunjung and Hyomin run away at 18 after the disapproval of their relationship from their parents. But, they break up and go their desperate ways after a year. What happens when Hyomin moves to Seoul five years later and discovers that Eunjung is her boss' new wife? 

Kim Taeyeon has a crush, Kwon Yuri and Kim Kibum make a bet, and somewhere along the way, Jessica Jung realizes maybe she doesn't hate Taeyeon as much as she thought. High school can't get any simpler than that, now can it? AU Taengsic.