1 - 20 of 2,826 Works in Ecto-Genitalia (Undertale)
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When you were ten years old, your parents sent you to stay with a relative of yours from Ebott. Their villa was situated up on the mountainside, and you loved to explore the forestry. One day the ground gave out and you fell Underground, and faced terrors beyond your imagination. You were missing for weeks.
After you managed to miraculously return to the surface, your parents were relieved - but deeply troubled by your 'delusional ramblings'. They were convinced you were 'crazy', and feared how that would reflect on their reputation. Your doctors advised sending you to an in-patient psychiatric facility, which is where you spent the next few years in intensive therapy and counseling.
15 years later, you're a young adult with a somewhat manageable grip on life. You keep your head down, attend the social events that are expected of you, and try to be as unnoticeable as possible. Your parents arranged a suitor for you, and you're to be wed within the next year.
That is, until, those monsters your parents and doctors tried to convince you weren't real suddenly crawled out from the Underground. And they're a lot different from what you remember.
[[Underfell!verse.]]
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Red Bones (Uf!Sans) won a scholarship at the St. Wendell Ebott University, a secluded University in Maine, and goes abroad to study at the Tōkyō Rika Daigaku (Tokyo University of Science) to become a Bachelor of Science. With his late father’s last savings, he flies to Tokyo and takes residence there.
Sans Serif (Ut!Sans) is offered a position as a teacher at the prestigious Tokyo University of Science. Having won a Nobel Prize in Physics 20XX for his findings in quantum physics, studies of multiple alternate universes and The Void. He is ready to impart his wisdom to the masses as a part time professor.
What happens when these two collide?
Drama unfolds!
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You and your family are just enjoying a nice day at the park, when a life changing event happens that ruins everything.
You get taken away to a facility to be tested on...
Life doesn't feel as peaceful as it once did, you hated your new life.
"I wish I could just go into those story books I used to read..."
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Diary of a Tired Afro-Latina who Decided to Date 14 Fuckass Skeletons at the Same Damn Time by BiblicalBeasts, sagemelons
Fandoms: Undertale (Video Game), Deltarune (Video Game)
18 Dec 2025
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When you agreed to move in with your datemates, you didn't think shit would be so damn chaotic. They argue over the dumbest shit and somehow manage to drag you into it?? Honestly, if the sex wasn't so good, you would've run for the hills already.
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A day in the life of Chara, Papyrus's Precious Pet.
- Language:
- English
- Words:
- 1,114
- Chapters:
- 1/1
- Comments:
- 1
- Hits:
- 159
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I’m safe here (I’ll wait for a brighter day) by Ultimate_Sugar
Fandoms: Undertale (Video Game)
18 Dec 2025
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Gaster introduces his littlest son to a brand new game they can play, just the two of them.
This can only go well, of course.
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You've found yourself attracted to a certain someone actively being hunted down in the Multiverse, whatever shall you do?
Well, thankfully, you know exactly what to do.
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It was done. His men would be busy for a week or so, maybe more; the mansion itself would be left just for the two of them. It was not a matter of space, but rather of privacy, and, following this, they'd have it in just the right amount and more. He had planned this— schemed this, even. He would not falter now.
Nightmare would attempt not to, at least.
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After weeks of planning, Ink and Nightmare finally decide to try whether fucking is as fun as it sounds.
Series
- Part 6 of There are other means of deceit
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Bewitched, Bothered, and Bewildered by CrimsonAndCloverOverAndOver
Fandoms: Undertale (Video Game), Mafiafell - Fandom
15 Dec 2025
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Cherry Sweet is a rather unconventional performer at a club like 'The Velvet Crop' with her thick thighs and plush stomach, but she does well enough for herself. The patrons enjoy a bit of variety, but what will she do when she attracts the attention of a monster--and a mob boss monster at that?
Featuring a 1920's vibe with music from the 20's-60's, a meet-not-so-cute developing into a partnership, and a spitfire, plus-sized FMC. I hope you all enjoy!
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Papyrus x Reader fic because I couldn’t find a good one to read <3 by FiddleStanLover67
Fandoms: Undertale (Video Game)
15 Dec 2025
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Papyrus and his Detective partner (you) have to solve a missing persons case. It turns into a huge undercover operation where you still have to rescue the missing person: Sans!
Along the way there's shenanigans, swearing, sex, misunderstandings, bad puns, and you fall in love with your spiky partner's brother. -
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Sans did not remember his previous name, only that he had been human. Rebirth in Undertale was novel, but he adapted, until he realized that the universe he was in was not the original one.
Unfortunately, it was too late when the machine took him to another universe, into a room full of skeletons.
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Sans no recordaba su nombre anterior, solo haber sido un humano. Renacer en Undertale fue una novedad, pero se adaptó, hasta que cayó en cuenta de que el universo en el que estaba no era el original.Lamentablemente, ya era tarde cuando la máquina lo llevo a otro universo en un cuarto lleno de esqueletos.
Nota: Sé que suena como tragedia, pero en realidad es una historia bastante esponjosa de curación, o al menos eso intento. Nuestro protagonista tiene mucho trauma y lo va a sanar en una mansión llena de esqueletos incómodos
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There was no hope.
There was no way out of this place. Sans knew that from the depths of his soul- he couldn't escape on his own. But without any way to contact anyone and no knowledge of where he's trapped, all he could do was try to survive... or maybe just hope for death.
No more resets, after all.
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You honestly can't remember when you had officially moved into the lodge to be with your datemate. It started as leaving things in his room under the (flimsy) excuse of having stuff for the next time you have an impromptu sleepover—but it was a not-so-subtle takeover.
The others didn't mind it either and were gracious enough to provide you with your own room for when everyone's shenanigans prove to be too much for you, but little did they know that they practically invited the devil herself into their home, because you're the queen of starting some bullshit or doing things for the bit.
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You are a passionate artist who’s struggling with sketching the pelvic bone, lucky for you, Edge is more than willing to give you some help and… his virginity?
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Missions are almost always demanding. Dust almost always comes back mentally exhausted and covered in remains. So, he seeks you out for comfort and relief. What happens when he finds you sleeping?
Series
- Part 4 of please get these fuckers outta my head
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Ink meekly replied "What if... We can create and destroy without fighting?"
"How the hell is that going to work!? We're just destroying and recreating the multiverse over and over again!"
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Ink and Error finally find a solution to a problem that only creates more problems.
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So you got woken up in the middle of the night by your new neighbors... no biggie! You're sure they're just excited to be in a new (cheap) apartment. So you decide to introduce yourself to them when they get settled in.
But to your surprise, your new neighbor just so happens to be a skeleton!
"Oh!" You say, surprised by your neighbor's appearance, "Uh hey! Welcome to the unit, I'm your neighbor"
"oh! hey i'm sans" He smiles, lazily copying your initial reaction.You hold your hand out to shake, he looks at your hand for a moment before accepting it.
when all of a sudden...
PPPPPPRRRT!
Was that a... whoopie cushion in his hand?
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His men made him too soft. It was dangerous, he knew. But he couldn't make himself care—even if it might have been a bit selfish.
(or; killer is angsty and his partners are great)
Series
- Part 5 of bbq writes smut
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Kinktober 2025 centered around Jannik Sinner and Carlos Alcaraz
Day 1 - Masturbation
Day 2 - Coming Untouched
Day 3 - Threesome (Clone fucking)
Day 4 - Voyeurism
Day 5 - Dacryphilia (and Cage)
Day 6 - Outdoor sex / Humiliation / Intoxication
Day 7 - Chastity
Day 8 - Webcams
Day 9 - Exhibitionism (and Puppy Play)
Day 10 - Oral Sex
Day 11 - Cum licking
Day 12 - Sissification
Day 13 - Dom!Bottom/Sub!Top
Day 14 - Omegaverse (Alpha/Alpha)
Day 15 - Pollen Sex (Sex Gummies)
Day 16 - Uniform (Firefighter)
Day 19 - Sensory Deprivation (+Wax)
Day 20 - Golden Shower
Day 21 - Monsterfucking (Part 1 of 2)
Day 22 - Monsterfucking and Quiet Sex (Part 2 of 2)
Day 23 - Praise kink and Biting
Day 24 - Gags
Day 25 - Impact Play
Day 17 - Birthday Boy ! (Massage + Surprise)
Day 18 - Size Queen
Day 26 - Lingerie (+T4T)