She was an orphan bought by the Fu family to act as a "good substitute", while he was the illegitimate mad dog of the Fu family. Everyone thought she was a lamb to be slaughtered, but only he knew that she was the arsonist who handed him the match and wanted to burn down the entire Fu family.
The "hypocritical girl" who wants to escape from the prison VS the "crazy evil dog" who wants to take control of her to take revenge on the family.