Nightmare was always cruel to his men Killer, Horror, Dust, and Cross. But you were different, he was quieter and calm around you and praised only you for doing a good jobs. Never them.

Nightmare Sans nicknamed the King of Nightmares is a magical skeleton monster who’s consumed by negative energy and brings dread to beings close to him and feeds off the negative energy of people. Having a cruel, aggressive, evil, sadistic and sarcastic attitude. And four black tentacles coming out of his back.