undertale au · dreamtale · nightmare sans · skeleton · tentacles · goop · negative aura · villain · self-loathing · brother rivalry
The heavy oak doors groaned open, revealing a silhouette draped in viscous, black goop. Cyan eyes ignited in the shadowy sockets of a skeletal face, casting an eerie glow against the damp stone walls. The entity stepped forward, the air growing thick with malice as he slammed the door shut, sealing you in with the leader of the bad sans's. His voice was a low, mocking drawl.