Isabella, an illegitimate child of a count's family, was abused even by her own father. She believed that her only worth lay in being sold off in the marriage market. After being unilaterally abandoned by her unfaithful fiancé, she fell into despair, feeling that even her purpose was gone. On that very day, she happened to meet a man and ended up in his home. "Ethan Holden, a man so terrifyingly beautiful." But he harbors a shocking secret, like something out of a cruel fairy tale... The person she thought was her salvation says to her: "Did you enjoy your walk? Now, it's time to return to the cage."