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  • Your Life?! (UF!Sans X Reader)
    51.6K 1.5K 8

    WARNING: Lots of swearing, blood, cruelty and slight sexual themes!!!! Sans and Y/n are arch enemies. They can't go a second without insulting the other. But one day an...accident happens, forcing them to co operate until they find a sulotion to their "situation". But before that, they learn a lot about each other and...

  • Northern Downpour (Underfell Sans x Reader)
    173K 5.1K 42

    (Y/n) goes to Mt. Ebbot in search of her brother Frisk. But what she finds instead amazes her.

  • Lost {Underfell!Sans X Abused!Reader}
    26.9K 776 6

    You were being abused. You couldn't take it anymore. But you also couldn't leave your kitten, Millie. So you gently put her in your backpack and got going. Your father wasn't looking. He was drunk, anyways. He probably didn't even notice the window in your room being opened. You made sure to lock your door before you...

  • Corrupted Timeline: UF!Sans X Reader
    96.5K 3.5K 31

    While hiking with your family at Mt.Ebott, you end up falling down a hole in another world where you encounter monsters who want to kill you. Will you be able to change their hearts and bring back hope? Or will you be killed trying?

    Completed   Mature
  • Just Like Before (A Gaster!Sans x Reader)
    51.1K 1.5K 29

    ♦Highest Rank :#714 In Fanfiction! ♦ Y/N fell down the Hole of Mt.Ebott when she was 8 years old. She lived happily with Toriel and with Other Monsters. She has a best friend named Gaster!Sans.She calls him 'Gas' for short. They always play at the Castle where Y/N's home is. Y/N broke the barrier before she and gas be...

  • GasterSans! X Reader Chan
    33.3K 1.1K 21

    You're having flashbacks about the past and the life you had with real life monsters. You're feelings to one particular monster takes you to your limits, and you discover something extraordinary yet life changing. (sorry this sounds way better after one of my follows said it's really confusing so I'm sorry if it was)...

  • Pet names and bites (Gaster! Sans X Tempered! Reader) DISCONTINUED
    3.5K 157 8

    "Listen hear, bucko. I don't want to take any punches on your skeleton face,but if you don't shut the hell up. I swear to lucifer! You are dead to me! So don't call me, 'Sweetheart','doll', or anything else alright. Good day!" DISCONTINUED

  • Sans X Reader
    383 22 3

    Okay.. So this is my first story.. This IS NOT a lemon. but its kinda sexual so if your not comfortable with that kind of theme then read at you own risk.. or dont

  • Neko!Sans x Neko!Reader
    32.8K 1.1K 6

    Monsters came to the surface and Y/n could finally come out of her hiding spot. Y/n was a neko,mostly classified as monster. What happens if she meets a neko skeleton?

  • WolfTale (Sans x Wolf reader)
    75K 2.4K 9

    Love. Sometimes it's just so painful, especially when the ones you love are murdered right before your eyes. You can't help but wonder if your heart will ever be whole again.

  • 【Angel of Blood】Underfell!Sans X Reader
    211K 6.1K 51

    Description: Once a long time ago, the multiverses were doing what they would normally do and were getting along just fine. Suddenly, it changed. Y/N L/N fell along with their parents into the Underground. In this world, it's LOVE or love.

    Completed  
  • Not too bonely anymore.... (Gaster! Sans X Reader)
    1.3K 58 3

    You run away from your abusive alcoholic mother to find a safer home. Taking a rest in an Alleyway, someone finds you, and tries a humongous amount of times to flirt successfully with you. You try running away, only to be thrown over their shoulder and taken somewhere new.

  • I hate to love you ~Underfell!Sans x Reader~
    6.3K 163 2

    Prepare for crappy writing skills-

  • Human Again ~ Undertale ~ SansxReader {COMPLETED}
    44.6K 1.5K 26

    {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 th...

    Completed   Mature
  • I'd Give My Soul to You: Underfell Sans FanFiction
    114K 386 14

    At one time, the Underground was a nice place. Despite some vengeful monsters, most were harmless, kind-hearted souls. ... When a human fell down into the Underground, everything changed. The royal family took him in and raised him as their own along with their only son, Asriel. When a fatal accident occurs, and both...

    Mature
  • I'm not alone... (Underfell Sans X Reader)
    21.3K 540 6

    You fall down into the Underground, thinking your life was helpless. Now....you realize your life is helpless without him....

  • UnderFell Sans X Reader
    42.6K 691 7

    MEH just another function ha ha a so hope you guys enjoy! (^v^)(^v^)(^v^)

    Completed  
  • Do you Trust me? (Underfell sans x Reader story)
    37.6K 900 19

    Making friends with others may sound easy as you think! But the thing that starts betrayal is breaking their trust Hah! Got your interest? It better! Feelings are coming up your way....

  • <DISCONTINUED> H E A R T A T T A CK [Underfell Sans x Reader]
    12.3K 459 9

    You wake up on a bed of red flowers.As you find a yellow flower with a face standing in front of you.He warns you about TORIEL who wants to capture a human soul.But...it's too late.As she drags you to her home,you escape down a long black hallway.A skeleton called Sans captures you and locks you in his brother's shed...

    Mature
  • Ran into You (Ink!Sans X Reader)
    90.5K 3K 20

    -Starts with UnderSwap- You were at home with Chara, enjoying a regular day. Since you'd gotten to the Underground, you'd become close friends with many monsters, even if your soul was what was needed to free them. You were about to eat dinner with your friends when disaster whisks you away from your home and into a...

    Completed  
  • For Your Sake (Gaster!Sans X Reader)
    60.5K 3K 20

    THIS IS A SEQUEL BOOK!!! IF YOU HAVE NOT READ THE FIRST BOOK YET THEN GO FIND IT ON MY PROFILE!!! Anyway, now for the summary: After death, you hadn't expected much to happen. You fell immediately into a place like the void. You just wanted to reconcile for what you'd caused, but your heart had a wish of its own. You...

    Completed  
  • To Love A Demon (Gaster!Sans X Reader)
    106K 3.9K 30

    *Do you fear me? "N-No" *Are you sure? "Yes." *You will learn to fear me Heh. Well here we are! I hope you enjoy this sin. I'm going to take my time and let you learn to love the characters slowly. So if you're the ones who like lemon in the first chapter, this is not for you. *Don't worry sweetheart. It will be worth...

    Mature
  • ~Why do you care~ [Underfell Sans X Reader] [•COMPLETED•]
    238K 6.5K 51

    Warning: possible swearing, inappropriate humour, perhaps lemons? Idk. Just stop being a goody two shoes and enjoy the book, kid

    Completed   Mature
  • Blown Through The Rift (Gaster!Sans X Reader)
    244K 9.5K 35

    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 surpr...

    Completed  
  • Rescue (UnderFell!Sans X Reader Fanfiction)
    76.3K 3.2K 32

    It was supposed to be a search and rescue with your two closest friends. With your 'brother' Frisk missing now two days and that foster home giving less than a damn, it was up to you and your best friends to follow his one clue. But what happens when one little clue leads to a situation larger than life? Will you surv...

  • The Hell He Created (SansXReader)
    103K 4.4K 21

    Monsters have returned to the surface, but that barely concerns you. Your only focus is to work and stay in control. Don't feel, don't lose control. You've spent years perfecting this practice and you keep yourself cold to anyone who stands in the way. A new employee at your work- a joking little skeleton - has a diff...

    Mature
  • Irene high (mc diaries)
    126 6 5

    Aphmau has to move away and go to a new school and she meets a few people along the way maybe even one will be more than friends