Sans (Red) is a monster trapped in the nightmare that is Underfell. Brotherly abuse and the stresses of this world cause him to do the unthinkable, how will the Swap brothers react to the arrival of his broken mind? Possible trigger warnings? I don't know, read at your own risk. UnderFell and by extension Undertale doesn't belong to me. Go check Toby Fox's game on Steam for the original Undertale story! Criticism is encouraged!

((DISCONTINUED)) After Chara erased the timeline, everyone had to go somewhere. That somewhere for Sans just had to be the Underfell universe. The people of snowdin in this universe aren't very friendly, and when Sans bothers people by looking for his brother, he has to be saved by his Underfell counterpart. Even under the care of someone stronger than him, how long will it be before Sans perishes?

Sans is constantly abused by his brother and head of the Royal Guard, Papyrus. Sans runs away and manages to get himself dusted or so he thought... Sans wakes up in a strange world with alternate versions of himself and his brother. Welcome to Underswap, what will happen in this strange world as Underfell Sans continues his struggles of everyday life... WARNINGS: Swearing, Abuse, Rape and Slight Font-cest. If you are unfamiliar with Undertale, Underfell or Underswap then look it up and get back to the story.