

The events of the Underfell Alternate Universe, Asriel finds a human named Chara in the underground. Sans is shown to have met Alphys before, from when Gaster was the royal scientist. This is an Underfell fanfic about Sans doing some sly stuff.That ends up hurting Papyrus in more ways than one underfellfanfic. Sans pays Grillby with socks and it pisses Grillby very much but he still accept it to pay Sans's tab. Papyrus wants the best for Sans but gets very annoyed when Sans doesn't think he can be the best. He isn't flustered and isn't always angry, he's just very tired. He doesn't like puns but likes knock knock jokes, he strives to be the cool brother, and he loves mustard and relish. His body structure appears the same as his counterpart (besides his teeth).

His shorts have a yellow strip instead of a white one and he wears black/red/white shoes or red slippers, as opposed to his counterpart's light blue slippers. His shirt is a red color in contrast to the normal white shirt. Sans wears a black jacket, with the "fluff" at the collar being notably more ruffled than the original Sans'. He wears a black winter jacket with a jacket fur flame hood and a gray cotton hoodie, and a red sweater with a golden chain with black pants that have yellow stripes going down. His right eye is seen to be glowing red 24/7. He is a skeleton with sharp teeth, with one being gold. Underfell Sans looks very similar to his Undertale counterpart.
