An Oath of Mercy || UnderFell Sans x Reader - Silver - Wattpad

Story cover for An Oath of Mercy || UnderFell Sans x Reader by StrawberryMilkSnake

An Oath of Mercy || UnderFell Sans x Reader

StrawberryMilkSnake

Reads 27,183
Votes 967
Parts 14
Time 2h 49m

Reads 27,183
Votes 967
Parts 14
Time 2h 49m

StrawberryMilkSnake

fellsans flowey monsters papyrus readerinsert sans sansxreader texttospeech underfell underground undertale undertaleau xreader

One clumsy moment and a broken leg are all it takes to leave you at the mercy of the very edgy and very hostile monsters of the underground. Thanks to your knowledge as a doctor (and oath to do no harm), you're able to convince the Great and Terrible Papyrus to keep you alive. But how are you going to find your way back to the surface with a bum leg and a short skeleton that doesn't seem to like you? | 

- UnderFell Sans x Human Reader 
- Enemies to lovers but Fell is the only one hating 
- Your leg privileges are revoked, and Fell needs to wash his mouth with soap 
- Flowey is an equippable companion and decides to help you cuz he actually gets something out of it 
- My own interpretation of UnderFell (tho from what I've seen it doesn't really have a narrative anyway)All Rights Reserved

fellsans flowey monsters papyrus readerinsert sans sansxreader texttospeech underfell underground undertale undertaleau xreader

Table of contents

14 parts

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A Strange Feeling (Sans X Reader) by Sak423

Do not expect consistent updates as life gets busy 🙃. This is rated mature because of strong language. You are a 24 year-old in college and have loved Undertale since the beginning. You enjoy all the aspects of the game; the story, the lore, the music, the backgrounds, and most importantly the characters. You've started having a strange, almost malicious feeling related to the Genocide run and that creeps you out. So, you start a pacifist run and after a while, you fall asleep. You wake up in Undertale and thus begin your new journey. Through your travels, the strange feeling comes back, but as a different emotion. Perhaps the only one that can help you with this feeling, is a certain punny skeleton. (I tried my best I'm not very good at summaries 🥲.) (Also I am so sorry for the kinda weird writing this is my first time writing a story. So I welcome constructive criticism.) Started: January 26, 2025 Ended: ???

Soulbound || Sans x Reader by StrawberryMilkSnake

When a situation with a dying human ends up with you absorbing their soul, you panic (like any unprepared monster would). Suddenly Undyne is hunting you down, so you rope the mysterious skeleton next door into helping you. Which he does--in a very Sans way. And who knows? Maybe pretending to be his girl will pay off. | - Classic Sans x Monster Reader - Fake dating turns into real dating - One (1) very mysterious skeleton & one (1) very awkward reader - Papyrus is so sweet and innocent, I love him - Monsters really are in the wrong for killing children tho - I love happy endings and hate tension so expect an easy, relaxing read

Underfell Sans X Reader by QueenSandwich123

Mature audiences only Will contain violent scenes with gore and sexual actions as well as abusive actions, strong language like cussing will be included.. may contain little bit of yandere moments could be in this story and other disturbing figures as torture may be included. please read at your own risk and enjoy the story! 😁 Underfell Sans x Reader.. Are you human? Are you a monster? Are you both? You just a human with a unique soul? What's different about you? Out of all fallen humans why are you different? Can you really save the Underground? Find out what mysteries lie ahead.. I know it's a short story but hey, it's better than a whole series of books to end up with a bad ending.

Stuck Together (Nightmare!Sans x Reader) by rainbowlixur

(First wrote this on Quotev loll) Humans and Monsters. Most people despise monsters, but not you. In fact, you fell in love with one. A king. And a Human. Who knew that a monster made of negativity could feel love. Who knew a person could love someone like that. Who knew that you being a negativity battery, would lead to a love story. Who knew that *he* would fall for someone as simple as you. #3 in #nightmare - 5/23/22 #3 in #xsans - 5/23/22

Human Again ~ Undertale ~ SansxReader {COMPLETED} by fantafrisk

{THERE IS LEMON BUT READING IT IS OPTIONAL AND WONT AFFECT THE STORY} You've aspired to be a Monster specialist ever since the monsters had left the Underground. You leave on your first expedition to find as much information on each Monster as you could but then you're sidetracked when you wander into a cave, where the barrier once stood, though you didn't know it and helplessly wander into the Underground and meet a strange skeleton who really sparks your interest.

I'm The Apprentice: Underfell Papyrus X Female Reader by JaysDreamCatcher

EDIT: READER AND PAPYRUS ARE BOTH IN THEIR TEENS!! WARNING: BOOK CONTAINS SWEARING/CUSSING AND VIOLENCE Just before she passed away, my grandmother told me about the monsters who lived under Mount Ebott. My mother hated everyone. My father died in the war of the monsters. My grandmother decided to whisper to me: "Promise me, You will find, A better family. One who will love you, No matter their duties. I will love you too, I will be watching you. No matter your choice, Let me hear your happy voice." So that's what I did. Her words went through my head as I climbed the mountain, hoping that a monster could help me. - "Sans flinched as the shouting downstairs grew louder. The ropes around my wrist seemed to grow tighter as I struggled, hoping to break free from the monster stomping up the stairs angrily. As Sans stepped back, his door was smashed open. I took one long look at the figure standing there and instantly knew: this is why I am here." - (SLOW STORY! MANY SLOW CHAPTERS BECAUSE OF DETAILS)(COVER ART NOT BY ME!)

My Little Mutt (FS!Papyrus x Female!Reader) by OreoDaSkeleton

Hi guys! First of all I should mention that the story pic isn't mine and of course Fellswap belongs to its original creator. A young hiker, Y/N gets lost and accidentally falls into a pit while stumbling in the dark. She wakes up to find herself in a whole new world that was never spoken of before except in children's stories. That's when she stumbles upon Barb (aka Mutt) and makes her first friend in the underground! But other monsters that live here aren't so welcoming.

Bloodfall (An Undertale AU) by BlackStormWolf

Ever since the death of his younger brother. Things have gone downhill in the surface world for Sans. Alphys died a few months after Papyrus to a disease, Mettaton and Undyne, especially Undyne, had fallen into a depression. Flowey dissapeared into mt. Ebott, not to be found and Sans is fighting depression and insanity. One day, Sans discovers a suspect to his brother's death. A being that is trapping anyone who had either fallen into Mt. Ebott or stayed behind in snowdin for a while. Sans, along with Frisk and Undyne, go into the underground themselves to confront this being. They must encounter the Bloodfall that traps and kills anyone who dares pass by waterfall. (This takes place after a true pacifist run if one killed Sans in a Genocide run, but reset their game before getting to Asgore(I did this in a way to quit the Genocide route). This is if Frisk choses to do this the Pacifist way. I might make a Genocide one in Story Shorts. Also, My Sans is a human, but feel free to interprate him as a Skeleton if you ever choose to use this AU. Just credit me!)

The Real Me + You by KasiaKaliszka

You've been living in the Underground for the past 2 years as a powerful Spell Caster, you prefer living in the Underground than up top on the surface as you find Monsters to be better company but other Humans do pass through from time to time. Monsters can go up to the Surface but choose not too as Humans do not want them there and will attack them on sight but there are some curious Humans who will pass through the Underground and so to ease what ever discomfort they may have some Monsters can make themselves look Human. You the Reader didn't get to know all the Monsters, for the whole 2 years you just worked and relaxed at Waterfall until you met a certain Monster who changes your life and you change his.

My new pet Swapfell! Sans x Reader by SugarHallows

You fallen into the underground, lost, confused...and no memories, what will happen to you when you encounter monsters that want your soul? Swapfell! Sans x reader

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A Strange Feeling (Sans X Reader) cover

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I'm The Apprentice: Underfell Papyrus X Female Reader cover

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My new pet Swapfell! Sans x Reader cover

A Strange Feeling (Sans X Reader)

Do not expect consistent updates as life gets busy 🙃. This is rated mature because of strong language. You are a 24 year-old in college and have loved Undertale since the beginning. You enjoy all the aspects of the game; the story, the lore, the music, the backgrounds, and most importantly the characters. You've started having a strange, almost malicious feeling related to the Genocide run and that creeps you out. So, you start a pacifist run and after a while, you fall asleep. You wake up in Undertale and thus begin your new journey. Through your travels, the strange feeling comes back, but as a different emotion. Perhaps the only one that can help you with this feeling, is a certain punny skeleton. (I tried my best I'm not very good at summaries 🥲.) (Also I am so sorry for the kinda weird writing this is my first time writing a story. So I welcome constructive criticism.) Started: January 26, 2025 Ended: ???