A girl with supernatural powers, Ye Luo, accidentally made a contract with the Ninth Prince Cang Lanye, and gained the ability to forcibly summon the Ninth Prince. She also discovered that this powerful and mysterious Ninth Prince actually had two forms: human and half-demon. Ye Luo and Cang Lanye battled wits and courage around the contract, and gradually fell in love with each other during the alliance. However, in order to prevent the half-demon power from getting out of control due to the contract, Cang Lanye decided to stay away from Ye Luo and suppress the out-of-control power. The relationship between the two also faced a new crisis.
