I recommend "There's an Evil Man in the Family: The Tyrannical Male God Loves You Fiercefully" to you. The male protagonist is the Black Dragon Emperor who falls into the world of the female protagonist, and the female protagonist is the mermaid royal family hidden in the human world. The two of them had different identities, but they loved each other. The love that transcended races was also moving. I hope you like this fairy's recommendation. Muah ~😗