Search: gaster
23,362 stories
Gaster x Reader- Not Your Fault

You're a human who has fallen down into the underground. There you meet a certain skeletal scientist and his sons. Will you get close to the family or will you become their enemy.Loosely based on TheBombDiggity666 Dadster comics (which you should totally check out if you haven't already) and occurs before frisk's appearance.Also artwork is not mine~

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The Ghost Above Me (Gaster x Reader)

Even though the Underground is now empty, except for some people, you still stupidly managed to fall in the once prison for monsters.Who knew you would get away from the prison with someone following you behind your back?Who would have known an echo flower would have revealed too many things?Who would have known you'd fall in love again?Words count: 55.608

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Gaster x Reader

Pretty self explanatory. This takes place after the Pacifist route in Undertale. Through determination, Frisk was able to bring back Chara, Asriel (Asriel is Flowey per say), and Gaster. I believe that Gaster is the father of Sans and Papyrus. I also don't believe that Chara is evil. The monsters are on the surface, and although they are amongst humans, most humans have accepted them.

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Gaster One Shots 3

THIRD TIME IS THE CHARM![Highest ranking #98 in fanfic]NO IMAGES R MINE

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Light in the Dark (Gaster X Reader)

He went blind in a freak accident at the lab. Now all he 'sees' is darkness. Until.. he meets you.

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We Speak In Hands (Gaster x Female!Reader)

Gaster is the current royal scientist, set with a mission to break the barrier and free monster-kind from their underground prison. His loyalty and persistence to the task is clear, since he'll make whatever sacrifice necessary to complete it. However, even a perfectionist can be blind to some of their own flaws. Gaster has a habit of pushing things or himself too far. An accident occurs in the lab. Whilst trying to save him; one of his lab assistants, Y/N, gets injured. Burdening himself with even more pressure and guilt to fix it, Gaster thinks that doing all of her work for her will cover up the incident. Still, the sad reality is that the damage can't be undone. Well, Gaster ends up spending more and more time with her. As a result, both of them gain an entirely new perspective of the other, they aren't just another monster in a lab coat anymore.Hey! It's Oreo aka Writer~San! Undertale, it's characters, and it's fanart do not belong to me. However, the story does!!! I hope you enjoy it! (^w^)~

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Gaster OneShots 4

THAT'S RIGHT! #4!!!(No images r mine)DEAL WITH IT!

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SOULs {Fem! W.D Gaster X Male! Reader}

You are the elder brother of Frisk. I'll explain later.This book will not be updated for a while, sorry.Completed: December 2nd, 2020SC Book# 12

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Scientist - GASTER X READER

Hi guys! So this is actually my first time writing a adventure story (and xReader), so I am kind of sorry if it looks crappy!!******A long time ago, people were missing when they climb up Mount Ebott. They say there was magic, got lost, or even died. But when you discover the secrets of the mountain, you will get attached to it, and even maybe meet a new 'friend'...||an W.D. Gaster x Reader fanfic||•I do NOT own any type of artwork that is included here in the fanfic, all art goes to thier respective owners.•

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Darkness' Eternal Bride (Gaster x Reader)

WARNING: THIS CONTAINS HIGHLY MATURE CONTENT (BLOOD, VIOLENCE) READ AT YOUR OWN RISKMoney can change a lot of things.It can even change your destiny.Plunge yourself into a life of romance, science, disappearance and misunderstanding.________________"When you get better, I'd like to kiss you"...Gaster only wanted to conduct an experiment. He surely didn't want his life to be taken over by weird feelings.He also wanted the only thing he couldn't really have.He wanted you.What will he obtain? Will his research finally be completed? Or will he have to start another one?As for you, will you be able to move on from the past?Words count: 81.390Also contains mentions of nsfw [Rankings: #1 in #gaster (08/21/2022), #5 in #xreader (08/21/2022)]

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The Faults in Our Souls ~ Gaster x Reader (Under editing)

"Do you not want to go back home? To the surface?"°°°°°°°°°°°°°°°°"No."°°°°°°°°°°°°°°°°"Why?"°°°°°°°°°°°°°°°°"Because my home is right here, sitting next to me."_______________________You were used to the unfortunates of life. Everyone had them, it was normal, but life decided to take a lemon, freeze it, then throw it at your face. But, it wasn't like it was THAT bad...Until you fell into the Underground that'd been sealed for over a hundred years, of course.Friends along the way help you through the sudden changes in your life, and a bone-ified family as well.(82,110 words)(Undertale does not belong to me, only the characters I added for plot reasonings. You belong to yourself, of course.)

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Fallen Angel (Gaster x reader) OLD

OLD AND BADLY WRITTEN THE REWRITE IS POSTED ALREADYDISCLAIMER: The god figure created in this fanfic is purely fictional. He is purposefully made to be prideful and cruel and is not supposed to represent any god. I am religious myself and I did not intend to attack anyones believes with this book. An angel. Sign of hope for humans, yet a nightmare for monsters. Powerful, skilled and...beautiful. But what happens when one rebels against the cruelty towards monsters? What happens when she's banished to the underground, only with wings as a painful reminder of who she once was.What if she's found by the Royal Scientist? What if the nightmare every monster is scared about, is just as broken as they are? And what if she'd find something she would never imagine she'd find in the underground...love?*Cover edited by me. The pictures used in the story belong to their original creators. If any of them aren't okay with them being used, I'll take them down*Started: 21.12.2018Ended: 22.08.202109.03.2019-Number 1 in gaster!07.02.2020- Number 7 in undertale!25.02.2020- Number 4 in undertale!15.04.2020- Number 1 in undertale!11.10.2020- Number 1 in papyrus!03.06.2021- Number 80 in fanfiction!

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W. D. Gaster - An Undertale Story

It all started when W. D. Gaster became the Royal Scientist of the Underground. Many monsters knew him, some even followed him. But one day, he injected himself with DETERMINATION. It caused something bad to happen. But it all took a turn for the worst when he fell into his creation. When he fell into the CORE. When he found out the truth. When he drifted in the darkness. Forever.Undertale Characters and Undertale by Toby FoxCover Art by me.

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Meeting WD Gaster

Reader meets WD Gaster. Takes place before the monsters are freed from Underground. Enjoy.

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The void in my heart (Gaster X Reader)

You're a human girl, living on the surface with Frisk, who is your younger sibling. You one day find two children, who's been chased away from neighborhood to neighborhood. And with you're kind soul, you couldn't leave them to live in the streets. You take them in, and meet their father. But will one day, lose them, because of a war. There is some ErrorBerry, and PaperFresh in this too.

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Gaster Blaster Sans X Reader

The barrier has been broken for a few years now. Monsters and humans have been living in peace together . . . for the most part. There are rumors about a monster who can somehow change his appearance into a big, scary dragon like skeleton thing. His name is Sans, and as you find out, he's not really that scary, just scared. This is my first ever X Reader, so keep that in mind. Please be kind and if you have any suggestions, let me know! Also, I guess it's kind of a slow burn . . . Art belongs to me. I don't own Gaster Blaster Sans. If you like this story I'm also working on the back story to how Gaster Blaster Sans came to be. It takes place long before this story when W. D. Gaster was still the royal scientist. You can now ask Gaster Blaster Sans: https://www.wattpad.com/story/76026518-ask-gaster-blaster-sans/parts

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Eyes of Fire (Gaster!Sans x Reader)

(FAN FICTION BASED OFF OF VIDEO GAME 'UNDERTALE')His eyes were like fire. Amber. Dangerous. But they intrigued me. The flames of his soul danced and encased my heart. It was needless to say that I didn't mind.(COMPLETED)

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I'm...swap gaster?

Yeah sorry gained an idea on if someone became swap Gaster Also they may be apathetic or just confused on their feelings and MAYBE Autistic, I may be a bit wrong on apathetic or not completely accurate idk yetAnd it's a huge maybe on the autistic part it might be mentioned at some point or notI usually don't do this kind of story on something like using apathetic and perhaps autistic but i decided I wanted to try.And the maybe confused kind feelings is not knowing what they feel or if they even feel anything and all

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Cracks (Gaster X OC)

Skeletons are a rare and fickle species. Their marriage has been arranged since they were born. Will they stay together or will other sources tear them apart?

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Gaster x Grillby (Grillster)

The art in this story isn't mine (if i feature my own art i'll say low chance i will seeing I can't draw grillbys head) This is story happens before Gaster falls, but they are in the undergrounds and also after gaster fallsA GRILLSTER ONE SHOT BOOK NOWREQUESTS OPENAll characters and game belong to TobyFox.

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Blown Through The Rift (Gaster!Sans X Reader)

You were working with Alphys in the lab in Undertale when chaos strikes! In a freak accident, concentrated determination is mixed with an unnamed concoction and blow you through a dimensional rift. When you reawake, you find yourself in what seems to be the beginning of Undertale once again. Upset but not overly surprised, you make your way back to Alphys's lab... Only to find her lab assistant is no longer you! Working with Alphys now is a tall, punkish skeleton with two cracks in his skull and a snarky attitude. As they help you find your way home, will you find more than that? *I DO NOT OWN UNDERTALE OR GASTERTALE!!! I WISH I DID BUT I DO NOT! THIS IS JUST A FANFICTION!!*

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The Royal Scientist is No Fool (a Asgore x Gaster fanfiction)

The queen has left King Asgore after both of their children have died and the king has killed one human already. His majesty appears to be in a stage of long-term grief. The royal scientist notices and tries to convince the king that it's okay. But as he does so.... He starts to feel his priorities shift.(i DO NOT own Undertale or this ship. all rights go to the original owners)

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[COMPLETED] Gaster Gang x Reader Oneshots!

Ok I have never done a oneshot book before -_-WARNING: VERY SLOW UPDATESlet's get the first thing out of the way-I don't under any circumstances own:-The Gaster Gang by Bunnymuse-Undertale by Toby Fox-Any art-Any YouTube videos let's see which characters you will be shipped with--WingDings: Undertale-Swap: Underswap-Fell: UnderFell-Blindy: Newtale-Stars: Outertale-Maestro: Underbeats-SF: SwapFellI'll explain everything in the first chapterBaiiii!~

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The worst way (gaster Sans X reader)

Normal days in your huge...lonely....stupid house that was given to you by your mother and father. They gave you everything, but not out of love, just to get you out of the house. You were only 16, you could barely even drive. They bought you this house, bought you a car, a nice one, and gave you your uncles motor cycle. It was nice. Then they left this world. A ring, all you had left to remember your mother, and a necklace, all you had left of your father, and this stupid, stupid house. It was lonely. Now you were 18 and looking for a job. You had good grades, and everything you could ask for. Now all you needed was a special...someone.

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Kitten (-gaster!sans x reader-)

The monsters were freed from the under ground. The humans are racist toward the monsters but the leaders of the human race have decided to restrict any human or monster to harm another to prevent another war.

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To Hell and Back (Gaster x Reader)

"What's that look for? Are you perhaps unhappy to see me?""Oh no. Oh no, quite the contrary, my love. I've craved to be with you for the longest time"*****You were sure that you would have captured a Monster, at all costs. But were you sure that you would have captured not a Monster's body, but a Monster's heart?*****The Barrier is broken•Frisk has saved the Monsters•But not all things went according to plan..........It is renowned that Frisk fell into the Underground. They spared everyone, they had [Mercy] for everyone. In the end, they have chosen to be an ambassador for monsters, to represent them in front of all the other humans.Frisk was full of [Mercy].But the humans weren't as merciful as them.Humans completely forgot about Monsters, and now they had to deal with what they considered an ancient enemy, despite the Monsters' friendly intentions.What will Monsters do, if they suddenly are persecuted by Humans? Will they seek help? Will they search for old friends?...Was it reality? Or was it a true living Hell?Things always went according to plan, so why? This time, why did it have to end like this?You are a spy, working for the most powerful secret Organisation of the Human Government. Your job is to find your targets and bring them back at the Organisation, but if you have the order to, then you have to kill them.This time however...you underestimated the enemy.*****The new plan was quite simple: bringing him back in exchange for your freedom.Falling in love with him was not part of the deal though.*********Cover by Earth Garden on tumblr!!

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