Taeyeon is an orphan girl who has been left by her parents since she was 10 years old. after the funeral, Taeyeon met someone that will change her life. From the bad one to a good one, from a loveless life to a life with full of love. He's Byun Baek Hyun.

Baekhyun is a boy who changed Taeyeon's life. He's cute and handsome. He's so loyal. Well, you can said he's almost perfect. But still ALMOST. As we known that no one is perfect in this world. Including Baekhyun. Because he has a weak heart that make him got sick easily.

Finally after they reached 17 years old, Taeyeon and Baekhyun are officially in a relationship. Their relationship started from Taeyeon's sweet seventeen birthday. Baekhyun gave her a surprise party. It just a small party but it mean alot for Taeyeon. She's an orphan and no one can celebrate her birthday with her. Baekhyun is the first man who made her a birthday party. Baekhyun gave her a heart necklace and at the same time he confessed his true feeling to Taeyeon.

2 years passed..

Baekhyun's condition is getting worst. He need a new heart to replace his. If he didn't get it, there'll be no other way to safe him. He'll die. Taeyeon knew about that and she don't want it happened. She don't want Baekhyun die in pain but at the other side she won't saw Baekhyun suffer like now. So she decided to do something.

Something that will change Baekhyun's life and her own life..