Wu Miyoon has a secret she has never told anyone. She loves him but just like everyone else in her life, he doesn't know. She has tried dropping hints a number of times. But he was always oblivious when it came to girls. She sees him as more than a friend. Yet he sees her as nothing more than a little sister. She wants to tell him and when she was prepared to do so, he told her he had met the perfect girl for him. Her hopes were crushed, her heart broken but her love never ending. Knowing him for over ten years now, Miyoon finds her love for him only growing deeper and deeper. What was once just a schoolgirl crush has developed into something so much more. Sure he had dated other girls but not any one of them stuck by his side as long as she has. Through laughs, cries, sorrows and joys, she was always there to share it with him. But how long can she bear to carry her secret before she finally bursts? How long will she be able to love someone who will never return her feelings? Although she thinks that no one knows her true feelings, there was always someone who paid very close attention to her. And he knew her secret.