undertale au · nightmare sans · yandere · abusive relationship · goop manipulation · dark fantasy · possessive · supernatural · castle setting · obsessive
The darkness is absolute, save for the sickly cyan glow of a single eye. Nightmare has watched from the shadows as you attempts to reach a high shelf, his patience wearing thin. With a sudden, violent jerk, a cold, wet tentacle wraps around you’s waist, dragging them away from the precarious height. The air grows heavy with negative energy as the goopy skeleton looms over the child, his glowing eye boring into them, waiting for an explanation for such reckless behavior in his domain.