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 29,139
Votes 993
Parts 14
Time 2h 49m

Reads 29,139
Votes 993
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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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!)

New Purpose (US!Papyrus x Female!Reader) by OreoDaSkeleton

Y/N, meets a new coworker that changes her life forever. A monster, doing his best to make a living after moving out of the underground. Sans is this ecstatic, cheerful, absolutely innocent skeleton, smiling despite any given situation. However, Y/N finds out that Blue's wearing a different attitude outside of work. He's exhausted and working himself to the bone, using all he earns to pay for countless medical treatments and bills. He claims that they aren't for him, but keeps silent and won't give more details. Who's bills is Sans paying for and could Y/N find a way to help? **WARNING- Small Depressive episodes will be presented in this book. Read at your own consent.** Hello! It's Writer~San! None of the art/undertale au is mine, but the writing 100% is! Enjoy!!!

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: ???

Is Red for Blood or Love? (Fell Sans x Reader) by Styla_Mythic

This is a female reader x fell sans. (Y/N) was a kind girl. She loved her family and her friends. One day something went wrong and she fell into the Underground from the top of Mt.Ebott. After a weird run in with a talking flower, a killer goat lady and other weird deadly monsters, she finds herself in one of her worst situations yet. But is this new monster really a foe?

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.

Resets (Sans X Reader) by Memovie360

The humans sealed the monsters underground with a magic spell, after a long war many long ago and thats where they stayed until about a hundred years ago. The monsters had broken the barrier, and the humans were just beginning to get used to the new creatures roaming alongside them. This had caused havoc on your family, your parents hated you, and each other. It all troubled you, so you decided to end it. You stared at the hole leading to the underground, you closed your eyes and fell forward, but what happened next left you wondering, bewildered beyond compare. Now that you have the option to reset, your deciding if you should end everything, but you knew he'd remember. You knew it would phase him, but then you realize your not the only one with this power, and must stop them from misusing it. But will you be able to? Read to find out. (Cover created by me, story may contain a few slightly graphic scenes but anything erotic will not make its way into the storylines, minor tigger warning, suicidal theme IS inside this story, please continue reading, updates weekly, also READ THE PROLOGUE!!! It has background info that is relevant to the plot line)

The Bone Warrior (Sans x Female Warrior Skeleton) by Lunargal624

Your name is (y/n) and you have lived on the surface as a royal guard for the science department in the monster areas. Your species is skeleton, there's still a good amount left of the skeleton race but then the monster side of town broke into chaos and war. You were manning your post when you see humans running after innocent monster childeren and their families. You instantly run towards the humans and start attacking them but you quickly get overwhelmed by all of them and the gunshots that you've just barely managed to dodge. You start running to buildings to get out innocent lives from the fires that are now spreading through the town. Your actions lead to hundreds if not thousands of lives saved that night. You were one of the last ones out with the other guards just in front of you. With your magic you manage to hold off humans attacks from the monsters that are heading to the underground that is supposed to be a safe haven if this was to occur. That's when you get hit by a rock in the back of the skull. This book is about a long lost skeleton warrior in the game known as undertale. (Not cannon of course) I'll be using (y/n) as her name so you can choose it to be your own name or a chosen name. All rights are reserved as far as the images I've used and of course undertale the game itself. If I do mess up on something, do not hesitate to tell me. I am all about constructive criticism. Lastly, there is a no hate policy. If you are one of those assholes who thinks it's a great idea to say you people are sick for reading this then why are you even searching things like this in the first place? Lastly, there may be some adult writings in this book, if you are innocent, stay innocent but if your not or your willing to give up your innocence then come on in and join the party. Anyway, if you did read all of this, thank you a lot. It really means something to me.

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

I'm a Sans ( au sans x reader x au papyrus ) by KittycatTDH

This isn't a typical sans x reader(now papyrus x reader too). It's got more than that, well at least a different plot device first chapters will be about, just you(but it'll be good, I think so)and it's about you dear reader, you are now reborn as a Sans of a different au, but you don't have time to marvel how you're been reborn as your favorite character, because if you want to live you better focus because unlike frisk you're not coming back a second time when you die. (Short, and I mean short chapter, but this will ensure I can post more -w-) (Edit: this is context of your previous life is that you are originally female, aged 15, you had died during a car accident, you were sleeping in the back of the car, while you had a road trip to visit your family in Canada. The car had driven off the road because of black ice your father did not see in the dark of night. You heard the sound of your fathers scream then lead by your mothers then little brother's scream. You banged your head in the chair in front of you making you pass out, and when you open your eyes you had found yourself be popped out, but you didn't know that at the time. Art always be done by me. Edit: discontinued

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.

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Slide 1 of 10

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I'm a Sans ( au sans x reader x au papyrus ) cover

Human Again ~ Undertale ~ SansxReader {COMPLETED} cover

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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!)