The Silver-Haired Prince's Superpower Concubine

He is the demon king in the eyes of the world, cruel and bloodthirsty, decisive in killing, and has massacred cities and annihilated countries in rivers of blood. She is the useless young lady in the eyes of the world, timid and cowardly, and can be bullied by everyone. When he met her, the demon king transformed into a cute boy, pretending to be cute all day long and pestering her with all kinds of martial arts. The girl who has zero resistance to cute things expressed great pressure. Who can tell her why the bloodthirsty prince turned out to be a cute boy in private? When a cute boy meets a sinister girl, when the king of modern killers meets the king of ancient killers, who is the real king? !