Red Mask
- Reads 283
- Votes 35
- Parts 9
Ongoing26m
Last published Fri, Jun 19, 2026
Underfell is a dark and dangerous place filled with murder in violence, and Sans and Papyrus are the pinochle of it all.
So nobody would ever suspect Sans to come back after a lost bet.
Maybe you haven't seen all of what's under Red's mask, huh?
Request for Icecream_Shipper
All Rights Reserved
#12
underfell
Join the largest storytelling communityGet personalized story recommendations, save your favourites to your library, and comment and vote to grow your community.
You may also like
Resetting Of Life
Kyra falls into the underground, while there she finds that her connection to the monster realm goes deeper then she thought. Cover by @rykosen Undertale belongs to Toby FoxComplete
the Undertale Adventures
What, if you meet Sans and get a crush on him? You two would move into the underground and experience some funny adventures together! Get ready for: The Undertale Adventures ~PibsComplete
The One Thing That They Care About (Sans AU x Reader x Papyrus AU)
Y/n L/n. A special human with a special SOUL. Yes, her Soul Trait is something new. But other than her SOUL trait she has another secret. One day, while she was at the surface with Frisk and Sans. 6 skeletons appeared out of nowhere, making raging screams and chaos as maniac laughter filled the air in their wake. Soon they found Classic Sans with Y/n & Frisk. But when they saw Y/n, they were curious of how she can wield magic powers and be brave. Soon they took Y/N with them, to their castle. Will Y/n tame them? Or will Y/n fail and suffer the consequences? Involving a Bad Sanses x Reader x Star Sanses plot. Along with various Alternate Sanses. #1 in badsanses at 17/01/2021 #1 in ausanses at 31/01/2021 #2 (Out of 21.8K) in nightmare at 24/02/2021 #38 (Out of 48.1K) in undertale at 21/05/2021 #3 in (Out of 3.42k) Cross at 18/12/2021 #1 in Dust (Out if 2.15k) at 18/12/2021Complete
A Bad Change (An Original) UF san's and UF Papyres story)
Edge thought he was going to be back without Red knowing but when he stepped inside the house he didn't expect everyone and I mean EVERYONE to be there. They tell Edge to either be nice to Red or they would force him to. As anyone who was told that and especially Edge took it as a threat but before Edge could do anything, he was tied down. The next thing Edge knew he was taken somewhere and started to scream, shout, kick, and cry out from the pain before he passed out. When Edge and Red meet up again, Red feels something wrong, he was happy to see Edge again but he didn't act or talk the way Red knew at all. Red got a sick twisted feeling when he didn't see the shine in his eyes, a shine he always had...... The cover is NOT mine it's From kyoma1719.tumblr.com In this story, they will have some of their elements game things and looks. I just thought this was a cool fun story I made up. I have other stories that am writing so am putting up the parts that are done. It will take time to write it. so slow updates don't judge :/ What WILL contain- *blood *weapons. *swearing *fights What will NOT contain- *Smut *ships November 20, 2021 - February 21, 2022Complete
Just SING | Sans X Reader
--Long ago, two races ruled over Earth-- --HUMANS and MONSTERS-- --One day, war broke out between the two races-- --After a long battle, the Humans were victorious-- --They sealed the monsters underground with a magic spell-- --Many years later...-- --MT. EBBOT, 201X-- --Legends say that those who climb the mountain never return.-- What if the legend is real? And what if the legend was all wrong? Start date: 4-25-2017 End date: 1-14-2018 Undertale & Characters ~ Toby Fox Plot, Book & Cover art ~ Me You ~ Sans ;) (I do not know why, I just keep putting 'You belong to Sans'/'You ~ Sans in all of my Sans X Reader descriptions from this point forward.) (Warning: Mild language and uh... fangirliness? Maybe, I don't know if you humans think this something to fangirl over.) 1K [•] Date: May 20, 2017 5K [•] Date: July 27, 2017 10K [•] Date: September 6, 2017 25K [•] (probably wont happen) (and iT DID HOLY SHIT THANK YOU SO MUCH I CAN'T) January 16, 2017 50K [•] Date: August 19, 2018 (what the fuck???) 80K [•] Date: February 1, 2019 (y'all... what the HECK) 100K and #1 in the #sansxreader tag [•] Date: July 2, 2019 *wheezes* what the FUCK how did this shitshow get #1 in the fucking SANSXREADER TAG thank you????Complete
Your Fault ~ Underfell Fanfiction
{COMPLETED} Sans' life isn't easy, and living in an Underground society filled with torture, rape, and murder doesn't make it any better. Every single day is a struggle, and Sans tries so hard to fit in with other monsters and live up to his brother's standards, but sometimes it's just too much. Will Sans be able to pull through, or will the darkening thoughts that are engulfing his mind and Soul take control, and swallow him up into a void too deep and dark to ever imagine? DISCLAIMER: UNDERTALE is owned by Toby Fox. UNDERFELL belongs to the AU Community. COVER IMAGE edited by me. I do not own the original image. PLOT/STORYLINE belongs to me. The events in this story are not canon and are simply for the entertainment of myself and my readers. Any OCs mentioned in this story also belong to me. MATURE CONTENT WARNING: The events in this story contain mature content that some readers may find triggering and/or disturbing. Read at your own discretion. Thanks!!Complete
Fight or Mercy | Underfell x Abused! Reader
[2nd book] ((COMPLETED)) {Undertale AU - Underfell} [WARNING:ENDING AND PLOT IS VERY CRINGEY] "Long ago, two races ruled the earth, the Humans and the Monsters. One day, war broke between the two races. Many have fallen to serve their kind. Years later, the humans were victorious. With their magic, seven of their strongest wizards sealed all the monsters underground with a magical barrier. Only a human soul could pass. Mt. Ebott 201X, they say those daring enough to climb up the mountain.... never return. " "Leave them, Y/N! Run! " ___________________________________________ I'm a Undertale addict. I freaking love the story line and characters! One of my favorite AUs is Underfell so I'm finally making an X reader. Also, if there are wrong spelling or grammar, please tell me. I'm using GoKeyboard. Enjoy my Crappy 2nd book!Complete
Write A Note (Sans x Female!Reader)
It's only been a few years since monsters have been released from their underground prison. In some towns, monsters are welcomed with open arms. Others? Not so much. Y/N is a 22 year old girl that lives a pretty simple life. Sleep, eat, work, relax at her daily cafe, go home, sleep. Then the routine starts again. However, her routine is thrown off when she keeps running into a skeleton, supposedly named Sans. She would like to get to know him more herself, but there's one problem.. He doesn't talk. Of course, Undertale belongs to Toby Fox, not me lolComplete
Reset (Underfell Brothers)
Papyrus was doing his normal schedule, waking up in the morning, shouting at his brother to wake up, and if he is late, you know who is getting the beatings. Usually, Sans would be terrified however, lately Sans has been different. He woke up on time, never sleeps at the sentry and frequently does mistakes. When he does, he would often gave an apologetic smile, never once he be upset or scared or angry at Papyrus. What really happened to his Sans? - Not a Fellcest- All Characters belong to Undertale except for Captain Rogers.Complete
HM/EB: Forgiveness and Sacrifice
Sans has been beat and tortured for most of his miserable life, almost exclusively by his younger brother, Papyrus. But, what happens when Sans is ripped from what he knows? How will Papyrus react? And, more importantly, where will Sans end up? Papyrus has abused and belittled his brother for the majority of his life, unable to see just how much he had hurt the one person he cared about it his life. When he is lead to believe he has dusted his older brother, he loses all reason to live. What happens when he dies in Underfell, only to wake up in a completely different universe? Will have both HoneyMustard and Edgeberry. No smut, sorry :PComplete
Kyra falls into the underground, while there she finds that her connection to the monster realm goes deeper then she thought. Cover by @rykosen Undertale belongs to Toby Fox
More detailsContent Guidelines