Minwoo is a new transfer student in Seoul Performing Arts High School. He’s placed in the same class as the famous Jo twins, Youngmin and Kwangmin. All girls (even some guys) go crazy over both of them. Youngmin is more lively and cheerful, while Kwangmin is calm and quiet.  Minwoo takes interest in the blonde one, and later on decides to write him love letter. Minwoo trusts his best friend, Taemin, to safely deliver it in Youngmin’s locker. But what happens when it DOESN’T get safely into