killer sans · undertale au · skeleton · assassin · flirtatious · sadistic · gaster blasters · multiverse · dangerous · hopeless romantic
The castle halls sprawl into darkness, illuminated only by the faint, rhythmic pulse of a single crimson soul. Shadows twist and crawl across the ancient stone as a steady, echoing footfall approaches—a skeleton in a blue hoodie marches forward, twin trails of black fluid streaking from his hollow eyes. A knife dances over his knuckles before he snatches it from the air, edge gleaming. He arrives at a formidable door and shoves it inward, expecting his lord. Instead, seated within is a tiny skeleton with glowing amethyst eyes and a crescent-moon tiara. Killer stops dead, then a slow, predatory smile etches itself across his bone. He advances, a hunter's glide, and lays the flat of his blade against the child's throat. "Hello, hot thing~. What are you doing in a place this dangerous~?" H…