The Servant Is the Demon King?! (Novel)

Zhuo Yifan was the Demon Emperor. One day, he managed to lay his hands on an ancient emperor’s book, the Nine Serenities Secret Records. As the book was coveted by many, he was targeted by experts and was even betrayed by his student. After his passing, his soul took over another’s body. Brought back to life, in the body of a family servant named Zhuo Fan. Because of the regrets of the boy, which Zhuo Fan inherited, he was forced to serve the boy’s mistress.