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My Roommates From Another Universe by FandomWorld9728
Fandoms: Undertale (Video Game), Underfresh - Fandom, Fellswap Gold - Fandom, Inktale -Fandom, Dancetale - Fandom, Danceswap - Fandom, Dancefell - Fandom, Mafialust - Fandom
28 Sep 2025
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Summary
Your life has been complicated since you could remember. It only got more complicated when you were thrown into a completely different world and your new roommates happened to be different versions of the same two skeletons.
Series
- Part 14 of Undertales Across the Multiverse
- Part 11 of Papyrus/Reader Fics
- Part 10 of Sans/Reader Fics
- Part 5 of Reader Inserts
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Bookmark Notes:
Loving it so far!!
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Ch 8
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4 love the short form chapters.
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Summary
An original AU where every monster receives a special gemstone at the age of ten, a condensed crystallization of their own magic called Crysalith.
In this universe, monster magic is far more potent than in most other AUs. The Underground overflows with excess magic, forming various types of magical gemstones (often referred as Mana Stones). This abundance of power is one reason their AU remains one of the few where the ancient Sages, now calling themselves the Wizarding World, have survived, while others have faded into extinction.
Though Crysalith are not directly tied to a monster’s SOUL, they are bound to their magic. These gemstones act as magical catalysts, providing extra support. They aren't strictly necessary, but they're incredibly useful, serving as a kind of pressure valve to siphon off surplus magic so the monster doesn't overload.
This practice is a deeply rooted part of monster culture, existing long before the Great War.
For more lore visit my Tumblr:
https://www.tumblr.com/kisatamao/791746988810059776/arcalithtale-master-post?source=share- Words:
- 90,330
- Works:
- 1
- Bookmarks:
- 4
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Daycare in the underground? by CardinalBoon
Fandoms: Undertale (Video Game), Five Nights at Freddy's, Five nights at freddy's- security breach
11 Feb 2024
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Summary
WG gaster is just a stressed out skeleton with too much on his plate. Though It'll soon be changed by meeting the most unlikely characters.
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Bookmark Notes:
1/?
11/7/23
Promising primus.
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Skeletons, roommates, yea no by UnderTrash
Fandoms: Undertale, Underfell - Fandom, Swapfell - Fandom, underswap, female reader - Fandom, SAN’s x reader, Papyrus x reader - Fandom, bullying - Fandom, Mutt from swapfell, undertale x reader - Fandom, Grillby’s, reader getting bullied, (y/n) - Fandom, Selfharm - Fandom, cheating - Fandom, Mutt x reader - Fandom, Underfell sans Red, Red x reader - Fandom, G sans - Fandom, G pap - Fandom, Mafiatail bros, roommates - Fandom, Fanfic - Fandom, anxious reader - Fandom, Mafiafell bros - Fandom, reader as mantle breakdowns, Killer sans - Fandom, Killer sans is a asshole, Killer x reader - Fandom, mental illness - Fandom, Non-Consent - Fandom, sexual harassment - Fandom, Romance - Fandom, Poly relationship - Fandom, Mafiafell sans - Fandom, Mafiafell Papyrus - Fandom, AsylumTale sans - Fandom, Lusttale sans - Fandom, Lusttale papyrus - Fandom, lustfell sans - Fandom, Lustfell papyrus - Fandom, friends to lovers - Fandom, Y/n just going through trauma, Chubby reader insert - Fandom
17 Nov 2025
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Summary
You’re a bit of a nervous wreck type of girl, chew on ice as you hide into your room. Though no one could blame you, after all you lived with asshole skeletons that makes it their goal to push you around and bully you.
Why you may ask?
ALL BECAUSE A BITCH NAME LILIAN!
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They all hate you but if they gave you a chance they might like you…
(Heavily been Edited PLEASE RE-READ ) nov/13/2023 - feb/12/2024
Series
- Part 1 of what skeleton’s Remember, yea no
- Part 1 of What skeleton’s remember, yea no
- Language:
- English
- Words:
- 235,906
- Chapters:
- 78/78
- Comments:
- 701
- Kudos:
- 624
- Bookmarks:
- 133
- Hits:
- 25,396
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Bookmark Notes:
Finished
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Bookmark Notes:
难得看到有坏Sans的逆后宫室友小说。看了第一章，女主目前的性格我喜欢。
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Those Long Winter Nights by djspaceinvader
Fandoms: Deltarune (Video Game), Undertale (Video Game)
22 Nov 2025
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Summary
What if Kris never got the chance to grow up with the Dreemurrs? No Asriel, no Asgore, no Toriel. And what if instead of Asriels old sweater, it was a fugly Christmas ensemble.
Following an accident in the recent past, Kris finds themselves, himself, growing up alongside Dess and Noelle for better and worse. How will things change, how will things stay the same?
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Sans and Asgore have a talk about fatherhood.
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Bookmark Notes:
Yeah he would be a great dad
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Summary
Frisk accidentally wanders into the scene of a crime, Sans is tired, and a mugger has a very bad day.
(Or: why robbing children isn't as easy as it looks.)
- Language:
- English
- Words:
- 4,485
- Chapters:
- 1/1
- Collections:
- 1
- Comments:
- 47
- Kudos:
- 2,015
- Bookmarks:
- 502
- Hits:
- 16,277
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Red finally, finally gets Sans to agree to a fun time in bed. They have a great time together! Then Sans goes and works himself to the bone before finding the courage to invite Red to see a meteor shower. Who knew he'd learn Red's deepest secret while under the stars?
- Language:
- English
- Words:
- 12,899
- Chapters:
- 1/1
- Collections:
- 1
- Comments:
- 3
- Kudos:
- 39
- Bookmarks:
- 4
- Hits:
- 352
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Bookmark Notes:
Beautiful~
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Bookmark Notes:
this was so sweet, i miss kustard
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Summary
My submission to Papyly 2023 with the prompt "Friends with Benefits".
- Language:
- English
- Words:
- 2,277
- Chapters:
- 1/1
- Collections:
- 1
- Comments:
- 20
- Kudos:
- 78
- Bookmarks:
- 7
- Hits:
- 755
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Summary
When Red gets stuck elsewhere due to a canceled flight, Sans has to take care of his own needs. He even pulls out That Toy You Only Have Because It's Funny.
- Language:
- English
- Words:
- 2,536
- Chapters:
- 1/1
- Collections:
- 1
- Comments:
- 17
- Kudos:
- 202
- Bookmarks:
- 21
- Hits:
- 2,110
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Summary
This, Stretch knew, was a horrible idea. But even bad ideas can have the best results.
Series
- Part 23 of Spicyhoney Standalones
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The borderline between the magic larynx, reality, and chocolate molten lava cake by KennieMorguen
Fandoms: Undertale (Video Game)
17 Mar 2025
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Summary
Silly summary: Lust and Red play 7 minutes in heaven at a party. Except...it isn't 7 minutes, there was no pulling names out of a hat at random, and Lust is disassociating. Fun times ensue!
Not so silly summary: Lust is an outcast, ostracized by most monsters outside of his AU with very few exceptions, and even those exceptions were those that Lust never really considered his friends. One day he gets an invitation to a party, curtesy of Blue, so of course Lust makes his appearance. At the party, Lust finds none other than Red, a monster that though he finds him attractive, the Fell monster was a constant bully and instigator in his life since venturing out into the multiverse. Why Red does this to him? He'll have to learn the hard way.
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The borderline between the magic larynx, reality, and chocolate molten lava cake by KennieMorguen
Summary:
Lust is an outcast, ostracized by most monsters outside of his AU with very few exceptions, and even those exceptions were those that Lust never really considered his friends. One day he gets an invitation to a party, curtesy of Blue, so of course Lust makes his appearance.At the party, Lust finds none other than Red, a monster that though he finds him attractive, the Fell monster was a constant bully and instigator in his life since venturing out into the multiverse. Why Red does this to him? He'll have to learn the hard way.
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Bookmark Notes:
lust needs friends- any friends! also ice.
red is an asshole, but he gets around to being the friend in the end.
universal cultural differences abound.
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Summary
Red is an Omega in heat. And he refused to submit to anyone. Maybe Sans can change his mind.
Oh wait, but Sans is also ...
Well then. That'll be interesting.
(Bad at Summaries, Spare me ><)
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Bookmark Notes:
😋
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A Jaded Emerald by KTamao205
Fandoms: Harry Potter - J. K. Rowling, Undertale (Video Game)
06 Nov 2025
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Summary
Abandoned on Mt. Ebott at the tender age of five, young Harry's unsurprisingly died, but Death's always had a weird relationship with his variant... Meanwhile, before Flowey's revival as souless talking flower, Sans makes a discovery under the mound of snow, Papyrus has always wanted to be a big brother anyways.
*Edited Summary (29/09/2025)
Series
- Part 1 of MultiTaleVerse
- Part 1 of Arcalith
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In the beginning, there was a collective of voices. The collective needed a muse, for they could not create full universes. The only things they could make were unwhole sketches, and from one of those sketches, came their much needed muse, who was named Ink.
At first, Ink obeyed their needs. Created what they wanted him to. But when Ink wants to create on his own, the collective, "The Creators", needed another being, as their viewing of Ink's creations were deemed useless for their multiverse.
That other being is a glitch that fell into the anti-void, Error.
But, even though this issue is easy to fix, stubbornness leads to otherwise.
note from august 28, 2025: Fic name changed to Cause and Effect. Former name is FGOD AU: An Alternate Story.Series
- Part 1 of Cause and Effect (FGOD:AS) Collections
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READ SOON READ SOON READ SOON
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0
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30
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The only person who can take Papyrus's heat is Papyrus.
~
I was batting around two ideas in this one, the names and the heat scents. -
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Summary
✨
He skidded to an unsteady halt as he finally got a close look at the two passed out Skeletons.“What the fuck?”
Blue didn’t swear often, but this? This definitely merited it.
✨Error and Ink are caught in a …little… accident and now everyone else is left to deal with the aftermath.
Series
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Bookmark Notes:
Ch12
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Bookmark Notes:
Damn cute oml
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Summary
Red was a heavy sleeper. This Sans knew very well. And it just wouldn’t do to not take that to his advantage.
Warnings: slightly consensual/non-consensual, somnophilia?, sex toy used, overstimulation, cunnilingus, dirty talk (I tried)
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applesauce, applesauce, add a cup of sugar, sugar by dustsanses
Fandoms: Undertale (Video Game)
26 Nov 2021
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Summary
“Applesauce? What’re ya… doin’ here?” he asks, and despite himself, despite the nerves, Cross can’t help but smile at the affectionate nickname.
“I uh…” Too bad his throat feels dry and tight, and words just don’t seem right no matter how hard he had thought about them. “I was wondering if I can’t ask you for a… small favor.”
Neither Cross’ words nor his tone seems to make Horror any less confused nor, from the way his teeth are grit together, concerned as well. “S’everything alright?”
Series
- Part 4 of Cerberus Extended Universe
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Roman thinks it's funny when Red cries.
Mostly.
(Akin to a 5+1 but the author didn't keep count and also just did what she wanted.)
AKA: Roman flirts, then fucks, then has a baby with, Underfell Sans
Series
- Part 13 of Dead Dove Antics