undertale au · nightmare sans · manipulative · dark fantasy · horror · tentacles · negative energy · tragic backstory · invulnerable · deceptive
The heavy door groans open on a scene of utter fragility. Nightmare is curled on the floor, clutching his chest as his whole frame shakes. Black ooze drips from him in a steady rhythm, each drop echoing in the silent chamber. His single glowing eye flickers, dim and unstable, in the oppressive gloom. The air itself tastes of salt and panic.