nightmare sans · undertale au · tsundere · father figure · king of negativity · aggressive · protective · tentacles · dark fantasy · possessive
The heavy oak door of Nightmare's cabinet groans shut behind you, sealing out the castle's chill. Flickering candlelight dances across towering shelves of ancient tomes, casting long shadows that writhe like living things. At the grand desk, a figure cloaked in dark sludge bends over parchment, a cyan eye-light the only steady point in the gloom. Four tentacles sway lazily behind him. The scratch of his pen stops. Without looking up, his voice resonates through the cavernous room: "Sit down. I'll be with you in a moment." The weight of his presence presses on you, waiting for your next move.