Underfell Stories

A young human runs out of the ruins desperate to get to safety. She runs into the Skeleton brothers Sans and Papyrus. Before she can know what's happening her world is c...

[Completed] [[Lemon and Swear Warning]] [2019 Jan Note: This book dates back to 2017, where my grammar and spelling checks weren't efficient due to me being lazy. So I a...

Y/n was half human and half bird. She had a dark tone of s/c due to her 'disease'. Raven wings was a part of this 'disease', along with interesting eye colors. This caus...

Sans and Papyrus were your best friends until randomly they just cut off all contact with you. This went for everyone else in your life so it didn't really hurt that muc...

This is a story before the last human fell around the time Chara was still alive and well. Humans were not being hunted till the adopted prince's passing, however with a...

You're the Ink of your multiverse, and you don't even know it. Well, until you meet the Ink of another, along with Error. -NOTES- I made the cover! This obviously isn't...

A girl who has never seen the world outside of the lab sees it for the first time only to fall down into the underground. What will she find down there?

Sanses included will be...Classic, Swap, Fell, Swapfell, Ink, Error, Dream, Nightmare, Dust, Killer, Lust, Horror, and Fresh. Please be aware that the pronouns used for...

Moved from AO3 because of reasons! "You are the only maid (or worker in general) that serves for the Skeletal Household. It's a skele-ton of work, but you manage by...

Instead of kidnapping the Sans from Underswap, what if Error kidnapped the Sans from Underfell instead? Error x Red You know how Error steals stuff and leaves his garb...

{Yan! Ut! Various x Fell! Reader} [reader is Gender Neutral] [College! AU] [tw: yandere themes, obsessive and posessive mindsets. read at your own risk. i do not condone...

Papyrus was never one to really care for anyone, but there are times when his armor isn't so tough. Especially when it came to his brother Sans. (Art not mine)

What if someone died and became the tree of feelings from dreamtale? Well things won't stay the same, that's for sure. (Different everything etc, different personalities...

(m / n) (L / n) is a 19 year old boy and he is frisk's cousin, (m / n) always looks after frisk like his own sibling because since childhood frisk has always been treate...

What if..someone from our world was reborn as fellswap sans? But an accident when he was young leads to becoming blind for a long time and papyrus feels guilty about not...

Underfell Papyrus is viewed as one of the most ruthless monsters in the underground but what is really under that tough persona? Thanks to Tamqul on Deviantart for letti...

You're a human that has fallen into Mt. Ebott on the year where all humans dress as monsters...Halloween. So how will the monsters know if you're a human or not?

(Underfell AU) Sans, badly beaten by his brother, goes to his friend from the ruins for help. But with his injuries and his dissaperaence from Snowdin, what is to come o...

Geno is a lonely thief, resident of a small sea village. His past is covered in darkness. Somehow he can't recall who he was or his parents. He only had his 2 younger br...

Long ago, two races ruled the Earth: HUMANS and MONSTERS. One day, war broke out between the two races. After a long battle, the humans... wait no, the monsters were vic...