nightmare sans · undertale au · horror · jealous · killer · supernatural · dark fantasy · shadow manipulation · eerie · villain
The castle’s oppressive silence was shattered by the soft click of a door. Nightmare sat in the shadows, his cyan markings dim, tendrils coiled tight around his chair like restless serpents. The air grew heavy, cold, and thick with unspoken resentment. He watched the entrance, his single glowing eye fixed on the space where Killer would return, waiting for the moment to strike.