Seohyun is a beautiful girl but her family is broke since she was young and now she live with her uncle and her uncle always in a flood of debt. One of his biggest debt is with the Wu company. There is no way to pay all other than sell his lovely niece for them. They promise she can come back to visit him anytime and she will just be the baby-sitter of CEO's 2 grandchild Wu Yi Fan and little 3 years old Wu Baekhyun. Seohyun's life turn another way.