1 - 20 of 2376 Works in Underfell Sans (Undertale)

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  1. Tags
    Summary

    Papyrus is dead. Frisk can't reset. Sans was losing his mind. His only solution was to pull through alternate versions of him until he finds him again.

    Unfortunately, you're the one in charge of babysitting your best friend and his dead brother's alternate versions.

    Series
    Language:
    English
    Words:
    233,079
    Chapters:
    34/?
    Comments:
    821
    Kudos:
    1720
    Bookmarks:
    392
    Hits:
    56410
  2. Tags
    Summary

    Dr. Sans Serif has been chosen to conduct an expedition to a newly discovered planet. There's a lot riding on this expedition; what Sans finds on this new planet could change the course of life on Earth.

    It’s a six week journey aboard a ship that is crewed largely by minimum risk offenders looking to trade labor for a commuted sentence that are kept in line by a group of soldiers led by Commander Red Gaster. At first the Commander seems to see Sans as nothing more than an assignment, someone he was charged with keeping out of harm’s way both aboard the ship and at their destination. But as they get to know each other, Sans is determined to win him over, though he needs to do it without losing focus on what he's come this far to achieve.

    Language:
    English
    Words:
    18,700
    Chapters:
    187/200
    Comments:
    1598
    Kudos:
    485
    Bookmarks:
    34
    Hits:
    11505
  3. Tags
    Summary

    (Underfell)

    In the Underground, failure is not safe. Weakness is not secure. Every time Papyrus' brother goes out and turns cash into liquor, drinking himself into a stupor in front of every other desperate idiot in town, he’s practically broadcasting his death wish on national television. He’s asking to get dusted.

    That’s all, obviously. It’s none of Papyrus’ business why sometimes Sans can’t get out of bed in the morning. As long as he fucking does it. Sometimes Papyrus would rather die slowly than start his early-morning human patrol, but he still does it. That’s what counts.

    If it looks spotless, then it is.

    “I am going to fix you,” Papyrus says suddenly, without thinking about it.

    The couch squeals as Sans rolls over, his red eye burning a hole into Papyrus’. It’s a challenge. Papyrus doesn’t look away.

    “You can’t, but thanks for trying.”

    Language:
    English
    Words:
    2,468
    Chapters:
    1/1
    Kudos:
    6
    Hits:
    17
  4. Tags
    Summary

    Years after the monsters are released from Mount Ebott, humans are still struggling with this change and accepting them into society. With tensions growing on either side, Y/N a young man who's a sloppy drunk is thrown head first into the fray when a certain skeleton helps him after a nightly blackout. Will he find love and family in the chaotic household he's introduced to or will his tumultuous past and addictions stop him from finding happiness?

    Language:
    English
    Words:
    12,440
    Chapters:
    3/?
    Comments:
    2
    Kudos:
    33
    Bookmarks:
    7
    Hits:
    236
  5. Tags
    Summary

    Some good old Twins!AU "Fontcest"♥ As each of their respective universe "Sans" trying not to lose their shit around their adorable younger sibling(s)♥✨

    O~h the humanity!♥✨

    [[[Severe Canon Divergence: It's fontcest, bit it's also not fontcest, y'know? You'll find out as you read the story...]]]

    Language:
    English
    Words:
    17,157
    Chapters:
    12/?
    Comments:
    40
    Kudos:
    72
    Bookmarks:
    15
    Hits:
    2447
  6. Tags
    Summary

    ~did you buy a bitty and then realize you were a creepy fuc-
    *Error, you can't just say that to people!

    ~...ugh, fine. did you buy a bitty and then realize you couldn't care for it? do you need a tiny roommate who has big opinions? well, only bitties in the building is here for you.

    *We are the number one--
    ~only
    *--bitty shelter in the Ebbot area! Stop by and ask for me, Ink...
    *Error, you have to say the thing!
    ~... or me, error. this's stupid, ink. 's just us and blue. who else are they gonna ask?
    *Sans works the front sometimes!
    ~ok, fine. asked and answered.

    *Anyway! Stop by for all of your bitty-related needs!

    . . . . .

    { Ink & Error run the only bitty shelter in Ebott City. As such, they're the go-to team when bitties are in trouble. When the police bust an animal fighting ring that includes a bundle of bitties, they have their work cut out for them rehabilitating and finding happy homes for each of them and their, um, special needs while juggling their meddling families and their upcoming wedding. }

    A daily drabble written in 250 words or less per day.

    Language:
    English
    Words:
    22,145
    Chapters:
    90/?
    Comments:
    2590
    Kudos:
    636
    Bookmarks:
    63
    Hits:
    12517
  7. Tags
    Summary

    I rewrite a fanfic I wrote last updated in 2019.
    Blueberror accidentally becomes a cryptid.

    Series
    Language:
    English
    Words:
    814
    Chapters:
    2/?
    Kudos:
    23
    Bookmarks:
    1
    Hits:
    198
  8. Tags
    Summary

    The monsters are free from the underground, but they didn’t all make it. Papyrus, Sans younger brother is dead, leaving Sans to care for the two children he left behind. After a long night of work Sans finally relents and hires a nanny/housekeeper. Enter you, just another human down on her luck and running from her past. this job seemed like an easy way to pass the time and get paid until your past inevitably catches up to you. At least that’s what you thought until you started developing feelings for the strange skeletons. Now noises are coming from the shed at night and all these new ‘cousins’ keep turning up. Can you help Sans through his grief? What is he hiding? And what is with this new gaggle of skeletons?

    ************decided to update the rating to mature because, well, we all know where this is going.******************

    Language:
    English
    Words:
    95,659
    Chapters:
    30/?
    Comments:
    265
    Kudos:
    254
    Bookmarks:
    72
    Hits:
    7666
  9. Tags
    Summary

    𝐘𝐨𝐮 𝐝𝐨𝐧'𝐭 𝐡𝐨𝐰 𝐲𝐨𝐮 𝐞𝐧𝐝𝐞𝐝 𝐮𝐩 𝐢𝐧 𝐭𝐡𝐢𝐬 𝐡𝐞𝐥𝐥..𝐧𝐨𝐫 𝐝𝐨 𝐲𝐨𝐮 𝐫𝐞𝐦𝐞𝐦𝐛𝐞𝐫 𝐡𝐨𝐰. 𝐎𝐫 𝐚𝐧𝐲𝐭𝐡𝐢𝐧𝐠 𝐫𝐞𝐚𝐥𝐥𝐲..

    𝐀𝐥𝐥 𝐲𝐨𝐮 𝐤𝐧𝐨𝐰 𝐢𝐬 𝐲𝐨𝐮𝐫 𝐧𝐚𝐦𝐞 𝐚𝐧𝐝 𝐭𝐡𝐞 𝐭𝐮𝐠𝐠𝐢𝐧𝐠 𝐢𝐧 𝐲𝐨𝐮𝐫 𝐜𝐡𝐞𝐬𝐭 𝐭𝐡𝐚𝐭 𝐦𝐚𝐤𝐞𝐬 𝐲𝐨𝐮 𝐰𝐚𝐧𝐭 𝐭𝐨 𝐬𝐭𝐚𝐲 𝐢𝐧 𝐭𝐡𝐢𝐬 𝐡𝐞𝐥𝐥𝐢𝐬𝐡 𝐮𝐧𝐝𝐞𝐫𝐠𝐫𝐨𝐮𝐧𝐝, 𝐦𝐨𝐫𝐞 𝐬𝐩𝐞𝐜𝐢𝐟𝐢𝐜𝐢𝐭𝐲 𝐭𝐡𝐞 𝐥𝐚𝐳𝐲 𝐩𝐞𝐫𝐯𝐞𝐫𝐭𝐞𝐝 𝐬𝐤𝐞𝐥𝐞𝐭𝐨𝐧 𝐰𝐡𝐨 𝐲𝐨𝐮 𝐜𝐚𝐧'𝐭 𝐡𝐞𝐥𝐩 𝐛𝐮𝐭 𝐡𝐚𝐭𝐞.

    𝐀𝐧𝐝 𝐭𝐨𝐭𝐚𝐥𝐥𝐲 𝐝𝐨𝐧'𝐭 𝐥𝐨𝐯𝐞...

     

    𝐈𝐟 𝐨𝐧𝐥𝐲 𝐲𝐨𝐮 𝐤𝐧𝐞𝐰 𝐡𝐨𝐰 𝐦𝐮𝐜𝐡 𝐋𝐎𝐕𝐄 𝐡𝐞 𝐡𝐚𝐬 𝐟𝐨𝐫 𝐲𝐨𝐮~

     

    (𝐁𝐭𝐰 𝐭𝐡𝐢𝐬 𝐢𝐬 𝐦𝐲 𝐟𝐢𝐫𝐬𝐭 𝐬𝐭𝐨𝐫𝐲 𝐚𝐧𝐝 𝐭𝐡𝐞 𝐟𝐢𝐫𝐬𝐭 𝐜𝐡𝐚𝐩𝐭𝐞𝐫 𝐰𝐢𝐥𝐥 𝐞𝐱𝐩𝐥𝐚𝐢𝐧 𝐦𝐨𝐫𝐞 𝐝𝐞𝐭𝐚𝐢𝐥𝐬 𝐚𝐛𝐨𝐮𝐭 𝐭𝐡𝐞 𝐬𝐭𝐨𝐫𝐲)
    𝐄𝐧𝐣𝐨𝐲!

    Series
    Language:
    English
    Words:
    38,253
    Chapters:
    14/?
    Comments:
    2
    Kudos:
    42
    Bookmarks:
    10
    Hits:
    882
  10. Tags
    Summary

    A story set in and around the late 1920's, early to mid 30's with realistic hot takes of the time period. A simple immigrate monster of a man is trying to run his business while his forced Mafia friend say no. There isn't anything either of these two monsters will do to keep their own safe but its going to come to a point where they are going to have to get along. Magic, massive inner demons and a real demon make a semi realistic take of Mafiafell story interesting. The market has crashed, jobs suck ass and so does the mafia. The only way out is death. Let's fucking go.

     

    More to add to summary while I add chapters.

    (There WILL be graphic scenes of death and torture in this story, all of which will be motioned a head of time. This is your warning.)

    Language:
    English
    Words:
    39,088
    Chapters:
    6/?
    Comments:
    5
    Kudos:
    9
    Bookmarks:
    1
    Hits:
    146
  11. Tags
    Summary

    Sans had only meant to retrieve a few things from the old house that had been forgotten during the move to the Surface. Getting ambitious with his ability to bend spacetime lands him in an unfamiliar Underground that seems to take his stubborn optimism as a personal insult.
    -----
    Sans had been minding his own business when an unknown skeleton suddenly fell into his life. He might have been able to take that in stride -- if the shrimp hadn't let his association with Gaster slip.
    -----
    Papyrus takes a monster in need into his home and hopes the decision will not be one he later regrets. His house guest appears to be a bit funny in the head but ultimately harmless, and Papyrus will admit his curiosity has been stirred with the abrupt discovery of a third skeleton.
    -----
    TL;DR It's a Swap!Sans in Underfell story.

    Series
    Language:
    English
    Words:
    20,839
    Chapters:
    13/?
    Comments:
    23
    Kudos:
    138
    Bookmarks:
    17
    Hits:
    1720
  12. Tags
    Summary

    You have a roomate who is very optimistic. Said roomate is your best (and only) friend. Then, his rather attractive skeleton friends and their "cousins" show up for a place to sleep for time being while their house is renovated for space.

    Language:
    English
    Words:
    3,289
    Chapters:
    3/?
    Comments:
    10
    Kudos:
    48
    Bookmarks:
    12
    Hits:
    487
  13. Tags
    Summary

    You love pancakes. They're so easy to make. Let's ignore the 7 monsters glaring at you and watching your every move.

    Language:
    English
    Words:
    72,197
    Chapters:
    13/?
    Comments:
    206
    Kudos:
    827
    Bookmarks:
    170
    Hits:
    15962
  14. Tags
    Summary

    I thought there wasn't enough Underfell appreciation (Or I'm just dumb) so take this-

    Language:
    English
    Words:
    2,837
    Chapters:
    3/?
    Comments:
    1
    Kudos:
    13
    Bookmarks:
    1
    Hits:
    230
  15. Tags
    Summary

    Error can't, he just can't. fate is ruining his life. He doesn't want to do this forced job anymore. He can't take it anymore, he just wants everything to be over.

    fate found out and Error is terrified of what's to come.

    More for the ones he told than for himself.

    Ink realises he's not the only one suffering from fate. He's just as sick as Error is from his forced job. Bad time helping the one he hates because it just got him in trouble.

    fate will never go easy on him again.

     
    What will they do now?

    keep reading, to find out -
    --
    Forced... - The rescue
    10/? (so far)
    Recovery <3
    0/?
    =Confession=
    0/?
    Finally free
    0/?

    (FGOD error belongs to harrish6)
    Error: loverofpiggies
    Nightmare and Dream: Jokublog
    Ink: Myebi/Comyet
    Horror: Sour-applestudios-
    Dust: Ask-Dusttale
    Killer: Rahafwabas
    Cross: Jakei
    Blue: Community
    Red: Community
    Classic: toby fox
    (Art by me (Me Paina))
    (Story by me (Me Paina))
    (Undertale by toby fox)

    Series
    Language:
    English
    Words:
    12,087
    Chapters:
    10/?
    Comments:
    23
    Kudos:
    170
    Bookmarks:
    17
    Hits:
    4597
  16. Tags
    Summary

    This is based on a rp

    Ink adopted AU Problem (an OC, don't ask about the name, you may can call her Allie or Uri) and Swapfell. Since Ink is away a lot, Fell has to take care of Allie/Uri. Swapfell also takes care of Allie/Uri, but since Fell is somehow around more..

    Anyways, lots of angst
    Death and stuff lol
    There will be many OCs since this is based on a rp

    Language:
    English
    Words:
    201
    Chapters:
    1/1
    Hits:
    4
  17. Tags
    Summary

    May is trying to make her way through life undisturbed but with an unwanted ability to feel all emotions around her, she finds it impossible. Or so she thought before she met a certain skeleton that turns her life upside down.

    Language:
    English
    Words:
    184,003
    Chapters:
    36/95
    Comments:
    244
    Kudos:
    380
    Bookmarks:
    73
    Hits:
    11050
  18. Tags
    Summary

    It seemed like Sans and Red's schedules were conspiring against them, they rarely had time off together anymore, and it's been a while since they've gotten to hang out. Deciding enough is enough, Sans goes to fix this.

    Series
    Language:
    English
    Words:
    2,098
    Chapters:
    1/1
    Kudos:
    13
    Hits:
    53
  19. Tags
    Summary

    Sans put on an act. A persona. Smile. Make dumb jokes. Act stupid. Be lazy. It was useful at first. It made him friends. When he was younger, he struggled in that department, just as his younger brother did at the same age. While Papyrus struggled with over eagerness, Sans struggled with basic detachment. He was curt, and got bored easily. Friends dropped like flies because they weren’t very useful to him. No entertainment there.

    That’s when the act started. When Sans pretended he was failing classes he was exceeding and didn’t pick up on context clues in conversations he got rather crystal clear. And for sometime, it was fun. It became easy to make friends when the people around you were clueless to your thoughts, when you were nothing more than a walking stereotype that had the same dialogue.

    Then, when the universes opened, Sans realized he could pretend to be a different Sans. And he lets himself out.

    Nightmare is now interested in this new Sans behind the mask. And so are some other people.

    Language:
    English
    Words:
    8,024
    Chapters:
    2/2
    Comments:
    12
    Kudos:
    99
    Bookmarks:
    14
    Hits:
    427
  20. Tags
    Summary

    Red comes over to keep Blue company, and things don't go as planned. But they do Go.

    Language:
    English
    Words:
    1,492
    Chapters:
    1/1
    Collections:
    1
    Comments:
    6
    Kudos:
    22
    Hits:
    92

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