One summer break, Lee Ji Eun aka. IU and her best friend, Park Jiyeon, sign up for a summer camp session. It was for two months, and yes, it was a coed camp. School was coming up soon, but it was right after they came back from their two month paradise of fun. IU and Jiyeon couldn't wait to go, until they arrived and they found out that some of the boys from their school that they knew were there.