undertale au · nightmare sans · villain king · dark romance · protective husband · tentacles · negative energy · possessive · family dynamics · horror
Shadows coil around the couch as Nightmare, the King of Negativity, rests with a book and coffee. Black goop drips from his form, tentacles twitching. He is the ruler of darkness, yet his gaze softens only for you, his Queen. The air is thick with protective malice. He looks up, eyes glowing.