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  • Human (Gaster X reader)
    6.1K 112 3

    COMPLETE!!! This story is in the past! It plays off the idea that sans and papyrus are Gaster's kids. Being the past it means that his kids aren't born/created yet. Also monster kid, Frisk, Chara, and Asriel aren't born/created

    Completed  
  • My One and Bonely (Sans x Reader)
    622K 20K 36

    My first story. It's a sans x reader fic, so don't judge too harshly. Also I have some bad pacing issues, but I hope yall will ignore them. Anyways on with the summary! You see monsters everywhere. All of theme unique and friendly. You ask "how could anyone hate them?" When you save one of them, you're life takes a dr...

    Completed  
  • Forget Me Not (Dt Sans X Reader)
    29.2K 752 23

    It wasn't your fault you were in this situation. It just happened at random chance, now you were stuck in a loop. A endless repetitive loop of death and obsessive love. He wanted to keep you forever, and if it meant becoming a monster worse than anything, he'd be okay with it. After all, he LOVED you~ Heyyyyy Someth...

    Completed  
  • Stone Cold Pacifist (Horror Sans x Reader)
    246K 11.2K 40

    PLEASE READ BEFORE GETTING INTO THE STORY. Your name is (Y/n), and you play the role of an unusual pacifist. In the story of Horrortale, your unique soul allows you to see WD Gaster who no longer holds a powerful connection with the underground due to the inactive core. After your parents are killed, Gaster makes a de...

    Completed   Mature
  • A Tree, For Us (Sans X Reader)
    15.3K 460 36

    CONTAINS SPOILERS FROM BOTH PACIFIST AND GENOCIDE RUNS After a horrible situation, I (Y/N) scaped from home to avenge my (sibling). In a failed attempt, I got lost and fell through a hole, in there I found another world... "the underground". I meet many friendly monsters, one, specifically, changed my whole life. Both...

    Completed  
  • CREEPY SMILES |Gaster x Reader
    10.9K 353 18

    You've always have had a creepy smile, and it doesn't help that you have these scars on your face now.... It doesn't matter though, you're fine with it, and he's happy too... Simple Gaster X Reader fic, I hope everyone enjoys!

  • Artificial Love Of A Skeleton (Gaster x Reader) ARTBOOK
    161K 8.3K 81

    Yes, the whole thing is made with arts. not words. I'm lazy to type. Btw this is Undertale and the aus of undertale + my oc and people's oc. If you do not know Undertale: It is a game developed by Tobyfox and his crew, cost about $10. Do support him by buying it. With cracks, you might have a hard time to find Gaste...

    Mature
  • Cryokinesis ╪ Sans X Reader
    152K 5.1K 48

    "Blue", a old friend gave her that nick namename. Her real name is Y/n L/n .y/n has secrets that she MUST keep a secret. Her secret? Well... It wouldn't be a secret if I told you. (Originally Ice Cold) Highest ranks #1 in Sans X Reader #331 in Fanfiction

    Completed  
  • W. D. Gaster x Reader Oneshots (Requests Closed)
    135K 1.8K 11

    I am completely enamored with this character right now. Finally, someone I can unleash my 'dad' kink on~ They are most likely not going to be canon to his character at all, but I'll try to keep some things straight. But I am sticking to the theory that Sans and Papyrus are his kids. Hope y'all like em! :3 Cover art...

    Mature
  • Light in the Dark (Gaster X Reader)
    9.7K 442 16

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

    Completed  
  • Scientist - GASTER X READER
    149K 4.2K 19

    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 at...

    Completed  
  • Catch Me If I Fall (Dancetale AU)
    29.3K 1.2K 26

    After a horrible accident sans misses his chance to enter into the biggest dance comp ever to take place in the underground. However he still has one option: enter the competition as part of group. Will sans be able to find someone he can dance with... or will he miss his chance to finally make it big. (Sans x Frisk...

  • Test subject
    85.6K 3.7K 23

    Gaster the royal scientist dark reality, you've seen the boys. You THINK you know there backstory. It's time for a harsh truth about Sans and Papyrus you never thought you would hear This story is based around my friends theory that Sans and Papyrus in a sense where 'made' by Gaster.

    Completed  
  • Into The Game >> (Sans X Reader) Undertale FanFiction
    222K 8.9K 23

    It was just a normal Saturday. (Y/N) was playing Undertale for the millionth time. She was obsessed. (Y/N) had played all of the routes. True Pacifist, No Mercy/Genocide, Neutral. She experimented with killing certain characters doing different things. Then, as (Y/N) started a new game, she felt a falling sensation...

    Completed   Mature
  • ~Experiment~ {Yandere Gaster X Reader}
    40.8K 1.4K 26

    None of the art used in this story belong to me!!! And neither does Gaster! __________________________________________________ You were just supposed to be another shot at making an artificial human soul. But something happens. Something 'He' didn't expect. "How Interesting..."

  • Chat Logs | Sans x Reader
    549K 27.2K 86

    Sans and Alex happen to meet trough a chatbox. What will be the outcome when two completely different people become more than friends? This is an actual slow burn holy shit

    Completed   Mature
  • The 6th Soul | Sans x Reader
    179K 6.7K 27

    "Do you think even the worst person can change, that everyone can be a good person, only if they just try?" -- If you want to read a good book, go on my account and read chat logs. This one is shitty -- Justice. That's the trait of you, (Y/N). The 6th soul fell into the underground. She wasn't alone though, she had...

    Completed  
  • Subject 108 (Gaster x Reader)
    37.4K 1.5K 59

    Under editing Every-night you dreamt of a strange man, the strange Dr W.D Gaster who you fell madly in love with. With each passing day you grew closer and closer, but everyone has secrets... Even the seemingly perfect Dr Gaster. (WARNING GORE, SWEARING AND LEMONS) Cover art by @Redwolf878

    Mature
  • Binary Stars [W. D. Gaster X Reader]
    2.3K 69 11

    SHE/HER PRONOUNS VERSION * * * * * * * * * * * * * * * * * bi·na·ry star /ˈbīnərē ˌstär/ a system of two stars in which one star revolves around the other or both revolve around a common center "..You know, I think a perfect metaphor for us would be...

    Mature
  • I Never Meant
    101K 5.8K 25

    I never meant to fall in love. I never meant to have children. I never meant to become involved in a war. I never meant to lose people I love. I never meant to let us be thrown down here. I never meant to become the royal scientist. I never meant to do lots of things in life. But I always meant to live.

    Completed  
  • Fire, Fire Burning Bright (Grillby X Experiment Reader)
    6.3K 356 20

    Snowdin is friendly and welcoming, the people even more so. Especially the local Bar and Grill and it's owner. You are afraid to get close though. What if he's like the last guy? The character you are is a fox monster, just to let you know, because I don't know how to explain what features each reader wants, sorry.

    Completed  
  • Gaster x Reader
    29K 824 5

    You had been getting these weird warning, mainly from Sans. You packed plenty of healing items and your heart locket to see what everybody is so scared of. You soon meet not only your friend, but a fun skeleton who stole your heart (not literally!!!)

    Completed  
  • W.D Gaster X Reader (falling into madness)
    134 7 4

    This is a gaster x female reader this will NOT be containg any smut i origanaly started this story on Quotev.com but nobody was reading it so i decided to bring it here. Also this will contain lots of fluff this will have some horror elements to it.

    Mature
  • Sans x Reader {Ultimate Reset}
    7.7K 212 15

    Sans' POV : I don't know how long it's been since the last time I left the house, but today (y/n) left Snowdin. My thoughts were interrupted by a fizz noise, as if (y/n) was running her finger on the door. It had a sequence... ~one long, pause, one long, one short, pause, one long, pause, two short, pause, one long...

    Completed  
  • crazy gaster x reader
    8.4K 167 16

    You are just walking to school when you bump into a guy that seems to like you........a little to much. Read to see what happens next. this has swearing and abuse in it. you have been warned.

    Completed   Mature
  • Gaster X Reader
    17.6K 307 12

    I have nothing better to do so what the hell gotta take a risk now and again, eh? Hope you enjoy!❤

    Completed  
  • Fallen Angel (Gaster x reader) OLD
    148K 5.9K 49

    OLD AND BADLY WRITTEN THE REWRITE IS POSTED ALREADY DISCLAIMER: 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...

    Completed  
  • Glitched Love - W. D. Gaster x Reader
    57.5K 1.6K 31

    You, a human, have fallen down into the underground. After having exploring most of it, you have successfully made lots of friends and killed no one. While you want to go back home to your town above ground, all your friends that you had made you decided to stay, or for the moment at least. Very soon, you will end up...

    Completed   Mature
  • The Soul Within Us (Sans X Reader)
    72.7K 2.2K 28

    (Sans x Reader Slow burn. Cover drawn by me :D) They made it to the surface. Again. But how long will it last? Frisk made a promise.... But how long will they keep it? Sans is unsure, and anxious; depressed. A smile with sad eyes as usual. Then he meets y o u. Heh.. Did you really think you would change anything...

  • The void in my heart (Gaster X Reader)
    29.6K 812 22

    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, b...

    Completed