One

After a messy break up with her boyfriend of 2 years, Choi Seungcheol, Yoon Jiyoon's bestfriend decided that it was the time to move on. So, she brought Yoon Jiyoon to a party. But, what Yoon Jiyoon wasn't expecting is, out of all times, that she'll meet her ex husband, Hong Jisoo, for the first time in 5 years.