The novice witch, Su Muyan, is a descendant of the witch clan in Beiliang. According to the covenant between the royal family and the witch clan, she is betrothed to the ninth prince, Feng Luochen, who possesses a pure yang body but is least favored by the royal family. Before this, Feng Luochen's three previous royal brides all disappeared mysteriously, and rumors spread that they all perished at his hands. In order to unlock her spiritual roots and rescue her beloved Feng Qiyu, the eighth prince, who is held captive in Nanyang, Su Muyan enters into a "contractual marriage" with the Prince of Killing. With her lousy witchcraft and earnest sincerity, she gradually captivates Feng Luochen and falls in love with him. As she reveals the numerous conspiracies surrounding him, the two outcasts in their respective worlds redeem each other, awaken each other's potential, and protect one another on their journey to the peak....