Underswap Stories

1.2K Stories

The Story of a Reaper by Undertale_tRaSh_4U
#1
The Story of a Reaperby tRaSh
When made by his father, the god of death, he didn't know his purpose. All he could do was kill things on accident...he didn't mean to kill them, he just wanted a friend...
Can I Stay? (Underswap!Sans × Reader) by Fruityyloopz
#2
Can I Stay? (Underswap!Sans × Read...by Justmonika
[Prolong] My name is (Y/N). I have experienced many resets, so many I have lost count. The only people who remember are Sans, Flowey, and me. The monsters down here are...
Hero Time Trio (Bad Time Trio X BNHA) (On Hold until I could think of an ending) by ShadowChaser936
#3
Hero Time Trio (Bad Time Trio X BN...by Shadow Chaser
Bad Time Trio meets BNHA Disclaimer: I do not own BNHA, Or Undertale, or any of the AU or any of the pictures showed
The Christmas Party [Undertale Au's x F!Reader] by _Sansational_Sans_
#4
The Christmas Party [Undertale Au'...by Pᴜɴɴʏ Sᴀɴs
[Undertale Au's x F!Reader] Can be found in my Quotev Account --> @.FanboilingTrash | AO3 --> @.FanboilingWriter | Tumblr --> @.bdudette When Blueberry and Str...
Au Group Chat     Bad sans/Star sans/Others by DahRadSkeleDude
#5
Au Group Chat Bad sans/Star sa...by JJ_loves_Ruru
Kinda like discord but with the Undertale Aus this will be very stupid
Six Skeletons and The Waitress by ItsSwapPapyrus
#6
Six Skeletons and The Waitressby Teutonic
A picture perfect family hides the fact that your life is filled with manipulation and abuse. When you move away after high school, you encounter more than one skeleton...
Bitty Bones (My Little Babies) DISCONTINUED (Creating a New Book Soon) by Delta_Nickle
#7
Bitty Bones (My Little Babies) DIS...by Delta Nickle
this is a story about a girl who finds little bitties who were abandoned and takes them in little does she know that its harder than she thought and that the bittys won'...
Completed
Reborn as sans from UnderSoul  by KarmaAkabane425
#8
Reborn as sans from UnderSoul by Karma Akabane
I was reborn as sans from my own made up au. How did that happen? I have no idea. Luckily I was still a kid so I didn't have to act like how I made sans to act like but...
New Purpose (US!Papyrus x Female!Reader) by OreoDaSkeleton
#9
New Purpose (US!Papyrus x Female!R...by OreoDaSkeleton
Y/N, meets a new coworker that changes her life forever. A monster, doing his best to make a living after moving out of the underground. Sans is this ecstatic, cheerful...
Hidden for so Long (Sans AU x Reader) {Remake} by RandomWriter-Chan
#10
Hidden for so Long (Sans AU x Read...by Just Here & Thinking
Long ago, two races ruled the Earth: HUMANS and MONSTERS. One day, war broke out between the two races. After a long battle, the humans... wait no, the monsters were vic...
Naturetale : reborn as lavender  by KarmaAkabane425
#11
Naturetale : reborn as lavender by Karma Akabane
(As far as I know, no one has made a story about naturetale like this so..and the only reason why I writing one like this is because of fatal error part 5? Or part 4, go...
AU Sans X Reader One-shots by Little_Blue805
#12
AU Sans X Reader One-shotsby Blue
Completely female readers unless a request asks different. That's...really about it, enjoy!
i n t o y o u 『 AU sans x badass!reader 』 by kyothedinonerd
#13
i n t o y o u 『 AU sans x badass!r...by kyo
! Art is by aozukikawasemi on Twitter ! The bunch of skeletons were taken aback once they took in the unexpected appearance of who exactly? You, of course. You were mind...
Just Strumming Along || {Reader x AU! Sans ((and some Papyrus's!)) } by galaxcoffee
#14
Just Strumming Along || {Reader x...by ✨☕️
When (Y/N)'s grandma passes away, she moves in her grandma's beach house in Oahu with her ukulele. But what happens when she plays that ukulele by the sea and a "po...
UnderSwap Papyrus one shots by CupofMochii
#15
UnderSwap Papyrus one shotsby Mochi~
*Picture credited to rightful owner* One shots include fluff, and maybe lemons *Requests are Open*
Completed
The Life of Blueberry - (An Underswap Story) by BloodGumm
#16
The Life of Blueberry - (An Unders...by Samantha Stilger
Blueberry - Sans of Underswap. But is he so different from Undertale Sans? Find out as we view Blueberry Sans' life in the Underground. I don't know what rating is used...
Completed
Mislabeled Errors by CreepyFuzzyMelon
#17
Mislabeled Errorsby KyonEndel
Error had had enough. He didn't want to feel anymore. Day in and day out it was always the same. He wanted to finally make it all stop. What will Error do if he gets a w...
Defenseless (bitty bones x reader)  by AkummaNuu
#18
Defenseless (bitty bones x reader) by Red Evergreen
as Y/N is walking through the city on the way to their friend's house, they find a box with 3 bitties inside, one crying, one curled up sleeping, and one already trying...
Smiling is a Coverup(Depressed Blueberry sans) by BruhItsUni
#19
Smiling is a Coverup(Depressed Blu...by Elana Ruiz
Blue is always keeping himself busy, trying to run away from feelings he keeps catching on too. But it will always eat him up. He keeps acting weird and "not himsel...
Completed
Undertale/au x reader 3 by Broken-fnaf-fan
#20
Undertale/au x reader 3by Artsy is bored.
(New updated cover) Welp, since you all loved the first two books so much, I wanted to make another. NO LEMONS! ONLY FLUFF! Mostly female reader sorry guys. Mostly be...
Completed