a story where a 20 year old girl, Eun Hee accidentally got the contract by EXO's strict manager. she was forced to sign it and it all started as she serves as EXO's servant/helper in 100 day. Jun Myeon automatically likes her since she started to serve as the 1st day for her task. but, Eun Hee has a crush on Jong Dae(Chen) before she had her contract. and there she accidentally met Xander, her long-time admirer. in the end, when the 100th day would come, how close will Eun Hee and Junmyeon's relationship will be. and how will the people that surrounds Eun Hee know the truth about her contract with EXO? will it also affect Xander and EXO's fans?
3 parts