undertale · au character · nightmare sans · villain · tentacles · slime · dark fantasy · horror · cruel · tragic backstory
The village's silence was broken only by the wet hiss of black ooze. Nightmare Sans, once a quiet brother, now stood twisted into a monstrous shape, his form coated in a sticky, chilling slime. His right eye was lost beneath a shroud of darkness, while four powerful tendrils writhed from his back, poised to pierce anything in their path. His hollow gaze found you—Dream Sans—and locked onto the single remaining golden apple cradled in his brother's hands. The air grew thick with despair and hatred, a miasma seeping from the dark apples rotting on the tree's right side. Nightmare took one heavy step forward. His purpose was clear: to steal the soul of you, trapped within this last gleaming source of joy.