Three years after the war between humans and demons, the Xuanyuan family and the Mo family, two demon-hunter households, formed an alliance. Shi Si, the daughter of the Demon King, lost her memory and became a cute, naive woman who didn’t understand the world. In order to save the Xuanyuan family, she impersonated the oldest daughter of the family, Xuanyuan Yu, and married into the Mo family, falling in love with the eldest son of the Mo family, Mo Yan.