In SM Town, everyone treats each other as sisters and brothers. There are usually rules about the relationship between them. Kim Hyoyeon and Lee Hyukjae a.k.a Eunhyuk are bestfriend. But the Girls' Generation main dancer had a little secret that she didn't want to tell anyone. When Eunhyuk was getting ready to join in the army, Hyoyeon decided to write a letter in oder to tell him the truth about her. Will he