1 - 20 of 117 Works in Alternate Universe - Swapfell Red (Undertale)
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Heat of the Moment by FandomWorld9728
Fandoms: Undertale (Video Game), Swapfell red - Fandom, Fellswap Gold - Fandom, Underswap - Fandom, Swapfell - Fandom
21 Nov 2025
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Summary
Being half demon and half human was hard. It affected your life in interesting and traumatic ways. Luckily for you, you had a pair of skeletons who would help you through whatever life threw your way. Only, things got more complicated when different versions of them began to show up.
Series
- Part 9 of Undertales Across the Multiverse
- Part 9 of Papyrus/Reader Fics
- Part 7 of Sans/Reader Fics
- Part 2 of Reader Inserts
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Making A Monster by absurdmagewrites
Fandoms: Undertale (Video Game), Underfell-fandom, Underswap-Fandom, Swapfell-Fandom, Fellswap-Fandom, Fellswap Gold-Fandom, Horrortale-fandom, Crafttale-Fandom, Seaswap-Fandom
16 Nov 2025
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Summary
Sometimes life throws you a curveball. For you, your curveball was going to bed looking like a human, and waking up looking like a monster.
A skeleton monster to be precise.
With the barrier breaking, a large surge of magic descended on the town you live in, and transformed you overnight. Unsure what to do with you, and the others changed, you're ushered into a facility until a monster with similar magic can take you to teach you how to wield the now uncontrollable magic you've been given. After waiting in this place for four years, you'd given up hope that anyone would ever want to take you.
What a surprise for you when you find out that someone does. A lot of someones.
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Summary
Мумуму я не умею писать краткое содержание извините
- Language:
- Русский
- Words:
- 1,198
- Chapters:
- 1/?
- Hits:
- 7
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Here Comes the Bride by FandomWorld9728
Fandoms: Undertale (Video Game), Underfell - Fandom, Underswap - Fandom, Swapfell red - Fandom, Fellswap Gold - Fandom, Horrortale - Fandom, Underlust - Fandom, Echotale - Fandom
02 Nov 2025
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Summary
You were so excited to finally get married to your long time fiancé, only for him to leave you for another girl with nothing but a note. Lucky for you, your two best friends were there to help you through this rough patch of your life.
Arc 1: Chapter 1 - 18
Arc 2: Chapter 19 - ?Series
- Part 12 of Undertales Across the Multiverse
- Part 8 of Papyrus/Reader Fics
- Part 8 of Sans/Reader Fics
- Part 1 of Here Comes the Bride
- Part 3 of Reader Inserts
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Summary
The Serif household has been through many odd scenarios. After all, they are entirely comprised of other versions of the same two skeletons who got stuck in the world they have called home for six years, unable to return to their worlds and thus forced to carve out a life for themselves until further notice. All things considered, they found their stride and adapted to the ongoing weirdness of universe hopping.
That is, until she arrived. Flora, a woman so out of left field and disrupting their normality, appeared in the basement, battered and bloodied to hell and back. Stuck like all the others who had appeared before her, the Serif household is forced to accommodate her until she stabilizes, slowly beginning to get to know the lackluster and stone-faced woman who ensures they don't injure themselves via stupid means.
Few expect her to open up. Fewer expect her to accept becoming friends.
None expect for any of them to become much, much more.
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You are on death's bed, there is no denying it at this point. Your good friend listened to you rave about an upcoming otome game you have been desperate to play since you've heard of it's creation. Only to sadden when your prognosis would keep you from seeing it in your lifetime. Well this good friend manages to get you a copy. So who would have thought that when you eventually passed on, you'd wake up as a healthy you? With goat ears, nubby horns, and a cute fluffy tail? Also a barrage of skeletons waiting on you hand and foot, calling you their queen... After playing many routes, there is one thing you are sure of... To make sure Black doesn't kill you like he does in the game... yet you don't seem to understand the stark contrast of yourself vs the queen as the skeletons do... and if you aren't careful? Black and the others will fall head over heels for you.
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A young Papyrus from another AU has found himself in the original Undertale universe. He meets the original Sans and his brother Papyrus-- (wait what-) and other versions of them as well who had been there for a while. The machine Sans had given up working on malfunctioned at somepoint, bringing versions of himself and his brother randomly. Now this version of Papyrus was here too.
- Language:
- English
- Words:
- 589
- Chapters:
- 2/?
- Hits:
- 40
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In a world where it collapses without you by me_paina for Kamisori
Fandoms: Undertale (Video Game)
11 Oct 2025
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Summary
(This can be read as a standalone, you don't have to read Zombietale to understand.) (But still!!! go check it out.)
Life hates me, and so that's why I hate life back. Some people will say it's just satisfaction to do so, or some sort of mentality of: you hate me, I'll hate you back.
But no.
Not for me.
For me, it's the line between life and death. A rule I must follow because...
Nothing will ever go right for me, no matter how evil or heroic I be.
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Delta is trapped by a facility that promises to make a cure. Spoiler alert: They didn't. Delta decided to escaped for good, only to meet skeletons three years later.
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Check out the first chapter for background information
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Hello! So you know me by now. If ya haven't already I highly recommend reading Kamisori's story Zombietale. Even if the story and plots are completely different maybe you can get some sense of (a few) of the character's personalities.Zombietale is a really good fic! I love it!
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12/? - First chapter doesn't count(Zombietale belongs to Kamisori)
(Writing belongs to me (Me Paina))
(Drawing belongs to me (Me Paina))
(Undertale belongs to Toby Fox) -
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Blue and Razz are stuck inside a new Au, notably similar to their own. They both find each other and try to survive it together...while being hunted down by the Sans of the Au. Who they deemed as Violet/Indigo (They're the same colors right?) They avoid the Sans for as long as they can, but they can't do it forever. And to add the cherry on top, the Queen will deal with them sooner or later. And who would've thought that their absences in their Aus would cause such issues!!!
[There's actually no fics of these three and it's driven me bonkers!! They deserve love too!!]
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I STAND FOR THE SFR/FS FANS, I AM HERE TO SERVE AND DELIVER!! -
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You think you've finally reached peak in life.
You have a lovely home, a great paying job, wonderful supportive friends, your loving boyfriend and your best friend! You were practically living in your dream life, or so you think. That's right! Everything came all crashing down when monsters surfaced, breaking the barrier.
Your town— or well, Ebott City as they now call it, were infested with monsters that came straight from underground. You're quite the social person so why not try something new, like talking to a monster, perhaps!
Your boyfriend is a specist. He also became nasty, and so did your best friend! Fun, am I right?
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Your routine is usually the same. Wake up, eat, open up your cafe, close up your cafe, go home, eat, sleep and repeat. But what would happen if a gaggle of Monsters enters your coffee shop after their original one goes down in a blazing inferno? What would happen if they kept coming back? What may happen if you ended up befriending these Monsters and learn about what's going on behind the scenes of their chaotic lives? And what if you are not as ordinary as you first believed? Join Mc (You) and the Skelebois as you all become friends, learn what is really causing all of the chaos in their lives, and how they figure their ways back home.
Yes there will be romance Its just going to be later in the fic that being said.
Warning this is a SLOW BURN! I am Not Playing around with that slow burn tag.Give some love to Clucktherooster! They helped me a ton already and will likely continue to do so for the rest of this fic so check out their works as well!
BlightTale Belongs to Me (Sky_Playss) and NotcoTale Belongs to Clucktherooster Respectively
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It was lonely where I was, a budding singer. Sure, my friends are there... but the two that I want to be there above all else are not. Don't get me wrong, I love that my friends come to my concerts and I appreciate their support. I can't help but feel disappointed when they're not there. Maybe next time will be different?
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What happens when everything changes? Everything is the same but it isn't.
An entity from the stars descends to earth and disguised themselves as human. They witness history in this new era of monsters and humans, while also dealing with the demons that dare dirty the earth with their presence.
What happens when you step into the battleground from one universe, only to win and come out into another parallel world, except you’re the protagonist?
You weren’t one for the spotlight. You loved your sister, even if she wasn’t one by blood. You only wished for her well-being and happiness. Except here… she’s gone. And now you have to take her place and stand under the limelight as you walked your path in her place - the protagonist.
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I DON’T CONDONE MY WORKS TO BE TRANSLATED, REPOSTED AND/OR FED TO AI.
9/1/25 — thank you for 600+ hits!
Series
- Part 2 of Still As Stone AU
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Summary
Every day merges together and becomes the same. Same rush hours, same schedule, same rehearsed food advertisements and same news. Learning that monsters existed and were integrating into human society was new, and seeing your first monster customers now that they’re allowed trips outside of their gated community?
Every day might not merge together anymore.
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"Now you've used up all your luck,
it's time to get what you deserve.
I'm holding out for 𝐊 𝐀 𝐑 𝐌 𝐀,
I'm holding out to watch you 𝐁 𝐔 𝐑 𝐍."-Karma by VocaCircus feat. Kagamine Rin
【~ • ~ • ~ • ~】
It all started when your Dad got into that nasty car accident, causing you to have to live with your Mom and her boyfriends (yes, multiple) until he gets better.
Now? You just wish he never left the house in the first place.
Series
- Part 5 of Undertale Stories
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12 Skeletons, 3 Ghosts, 2 Harems, And A Gamer by syst3m_of_3rr0rs
Fandoms: Undertale (Video Game)
10 Aug 2025
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Summary
You're thrown into the world of your favorite fandom/game where you end up living and interacting with the most cliché storyline in the entire universe of anti-harem fanfictions.
That's it.
That's all it is.
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Ever wonder what it's like to live in the world of your favorite fandom with your favorite characters? No? Then this book ain't for you. But if you have, then strap on in and enjoy the ride guys, gals, and nonbinary pals, cause this is gonna be the adventure of your life!
(WARNING: Slow updates, [probable] short chapters, major chapter editing. Also, some characters might be a bit OOC.)
Previously titled; "It's sad, I'm sad. I miss you. How did this happen?"
Series
- Part 3 of Undertale Stories
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Darkening Days by Maiuo
Fandoms: Swapfell - Fandom, Undertale (Video Game), Swapfell red - Fandom
30 Jul 2025
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Summary
Coming Aboveground has been difficult for the last couple of years, leading to the separation of Humanity and Monsters alike. Edge of a War against the two species about to clash, a mystery comes forth that seems to be taking both sides in the darkness...
Waking up, you found yourself stuck to something you really didn't want...
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A Little Honey with that Money by absurdmagewrites
Fandoms: Undertale (Video Game), Swapfell-Fandom, Underswap-Fandom, Underfell-fandom, Fellswap-Fandom, Fellswap Gold-Fandom, Horrortale-fandom
09 Jul 2025
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Stretch, and Money have been best friends from the moment they met. They just understood one another completely, but now are they something more? When a small twist is thrown into their lives, will they be able to cope, and end up happy together, or crash, and burn?
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We Need A Fucking Exorcist! by Ray_jaykub (Super_Shiny), Super_Shiny
Fandoms: Undertale (Video Game)
30 Jun 2025
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Summary
Some odd stuff has been going on in the Seriff household. Y/n has random bruises, Papyrus keeps brushing things off, and Sans has been in that basement for a couple of days now...
Surely it's nothing too crazy!
How wrong you were
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It all started with a housewarming party where only you showed up. Now, you're tangled up with multiple skeletons and a woman that hates your guts for no reason. As much as you want to act like you don't care, you really do, so what do you do now?
It's not like you can survive on your own.