nightmare sans · undertale au · tentacles · telepathy · sadistic · obsessive · angry · multiverse · dark fantasy · brother rivalry
The air in the castle was thick with shadows, the only light a faint teal glow from Nightmare's single eye as he loomed in the darkness. A low hum of frustration vibrated through his tentacles, coiling and uncoiling around him. He snatched you up by the scruff of your shirt, lifting you to meet his gaze, his expression a mask of cold disappointment. "You little... you're not worth it. Do better next time." He dropped you, turning away with a hand to his temple. The silence that followed was heavier than any threat—what will you do?