My Sister Is a Demon

In this world, the Devil's representative, the Heavenly Demon Palace, monopolizes nine states, and the Great Yan Dynasty only has twelve states. For hundreds of years, wars between the two sides have been constant, good and evil are fiercely confronting each other, and the people are in dire straits. Mo Wangnian's soul travels here, and the female demon king who commands the world's demons is his sister. "Sister! I don't want to go back to Beihan with you and become a young demon master!" "If you keep nagging me, I'll take you back to Beihan!" "..."