Undertail Stories

376 Stories

Classic x fell (lemon) by JackPutman
#1
Classic x fell (lemon)by JackPutman
Plz give me suggestions of what to do next and if I don't upload for a while it's because I have important things like school homework and I'm probably thinking about wh...
Nightmares Little Gang by Tired1PanPan
#2
Nightmares Little Gangby Pan
Nightmare, The King of Negativity, known for being cruel and torturing people. But oddly enough he feels lonely, I mean it must be hard when his only friend Error is alw...
AU Sans X Reader one-shots by _PleaseDontGo_
#3
AU Sans X Reader one-shotsby _PleaseDontGo_
Want to be in a one-shot with the sans of your choice? Well you came to the right place!!! Just comment down below in one of the one-shots!!! Enjoy!!!!
Of a Better World by toast_and_bunz
#4
Of a Better Worldby toast_and_bunz
It's been a while since Horror's world could be considered even remotely kind. But a newcomer drops in, and reminds him that there's still sweetness to be found in life...
Falling in pun with you (Completed fontcest Story)  by Intellectualpan
#6
Falling in pun with you (Completed...by Jessica
A skeleton named Sans falls in love with the only thing that makes him happy, that made him feel complete... his brother Papyrus. But when sans suspects papyrus of falli...
You Make My Soul Flutter by SpareRib_Soup
#7
You Make My Soul Flutterby SpareRib_Soup
Yes another fontcest I know. This is currently a work in progress so please be patient with me. Word average of about 1000 words per chapter
"Not Quite Determined" Sans x Human/Monster Reader [COMPLETED] by FloweyTheGrouch
#8
"Not Quite Determined" Sans x Huma...by AsrielAs Flowey
You've lived your life without ever knowing your parents. Despite that you dream big because you don't have much; aiming to become a famous singer and prove anyone who h...
I'm Pickin Up Good Vibratons~ (Undertale Sin One-Shot) by DoodleWritesAThing
#9
I'm Pickin Up Good Vibratons~ (Und...by DoodleWritesAThing
Just a drabble :P This story will include 18+ content, if you're comfortable reading that then move along, but if you are younger than thirteen and still have not had...
omotale one-shots by WingedWhiteTIGER
#10
omotale one-shotsby Angel
this is full of omotale stories I write please excuse my Shity spelling and grammar this is NSFW I do take requests some fontcest
Don't Reset by Gay4Pain
#11
Don't Resetby I'm okay.
Howdy, this is a flowey X reader thing, I'll try to post often.
Bad Sans Poly Stuffz by Sapperz
#12
Bad Sans Poly Stuffzby SappySapperz
Ah here we go first time writing h a h. Anyways. Lil quick warning there will be -Smut -Fluff -Angst -And some kinks (For example size difference) If you do not enjoy a...
Secret Admirer by IAmADirtyDirtySinner
#13
Secret Admirerby IAmADirtyDirtySinner
Frisk always had a crush on Sans ever since they had left the underground. After she turned eighteen, she fantasized him of fucking her.
Forever mine- sans x nagito by jankofazulka
#14
Forever mine- sans x nagitoby jankofazulka
Nagito trying to get his true love back. --------------------- My and my friend were at school when we wrote this.
Completed
Various X Reader Lemons by MakingLemonades
#15
Various X Reader Lemonsby Writing smutty shit at fuckin...
(Comes back 4 years late w Starbucks and improvement) Hello! Welcome! Sin!
Chara x Frisk FLUFF by nochopie
#16
Chara x Frisk FLUFFby nocho
So this is just a cute little story about Chara and Frisk the ship is amazing And gay. <3
It's Not Possible ( Nightmare x Killer ) by jesus_davito13
#17
It's Not Possible ( Nightmare x Ki...by Abomination.
It's almost the end of highschool for Killer, an 19 year old student at a human and monster school on the surface. Killer isn't ready to leave the highschool yet as he's...
The Blue Hearted Hero (bnha x undertail fanfic) by crimson518
#18
The Blue Hearted Hero (bnha x unde...by Daniel Roberts
" why dont you just take a swan dive off a building and hope that in your next life you get a quirk " was the greatest advice given to the quirkless boy izuku...
A collection of bad fanfics by powermittens
#19
A collection of bad fanficsby End my suffering
A contest between friends I'm sorry you had to witness this horrible story.
Completed
Error Uke oneshots[REQUESTS OPEN] by CharlieEatsWaffle
#20
Error Uke oneshots[REQUESTS OPEN]by Waffle-Man, the gayest hero!
basicaly a big book of my favorite sans in my favorite role;Error as a bottom.