1 - 20 of 1,866 Works in Ecto-Penis (Undertale)
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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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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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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. -
(Please) be reasonable by Otaku_girl for HasBeenHellWolf (FelliSkelli)
Fandoms: Undertale (Video Game)
12 Dec 2025
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“Boss, please… c’mon, can’t we be reasonable about this?”
“I hear that you are out there, acting like a complete hussy on top of everything else! Just what do you have to say for yourself?”
“Boss, please. You could… you could remind everyone of who I belong to.”
“Oh, I’ll make sure nobody can forget who you belong to. Nyah-hah-hah.”Sans’s smart mouth gets him in trouble. Papyrus teaches him a lesson.
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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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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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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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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) -
Ah shit I didn’t think of a title by Ginger_Candy (Candy_Cryptid)
Fandoms: Undertale (Video Game)
29 Nov 2025
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“It’s embarrassing,” Dream wants to say, voice shaking through Nightmare’s fingers. His hips buck into Nightmare’s touch, and his sockets heat up in his frustration.
“It’s just me,” Nightmare answers, like Dream said anything at all. “What’s there to be embarrassed about?” -
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this is basically just me writing things about Wisp(my dust sans variant) and Gehenna(my friends nightmare sans variant)
- Language:
- English
- Words:
- 2,924
- Chapters:
- 1/?
- Kudos:
- 4
- Hits:
- 48
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A rewrite of a previous fic, changed structure and story and more Sans' to have sex with.
Years have passed since the barrier had fallen and freed the monsters. You had your found family with them, Sans in particular being your best friend and support. You heard of SOULmates and how monsters have them, you wondered yourself if humans also had SOULmates, and you find out as you begin to travel through different Undertale AU's just how SOULmates and SOULs work through the multiverse.
*I DON'T USE Y/N*
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It’s a very… delicate time of year. Or so you’ve been told; you can’t say for certain that you’ve ever been around a monster during their Season. Your stay at Nightmare’s castle has certainly prepared you for all manner of strange and unusual occurrences, but this?
This is a whole different beast.
Series
- Part 2 of PROPAGANDA
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What do you do when your boyfriend gets caught in the very trap he was trying to show you? Have a little fun, of course! And maybe figure out some new kinks in the process.
Series
- Part 6 of Papyton Smut
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The thing about soulmates is, no matter what pries them apart, they always...always find a way back together
Chapters 1-3: Prologue
Chapters 4+: Main Story
*This story has LONG chapters. I’m not sorry**This is a rewrite of I Have The Power of Gaster AND Anime On My Side. Same concept, with a bit of a serious feel.*
**Please be aware that this is not like my usual reader-inserts!! This story is in 3rd person pov, very vague description of a female reader. Unnamed (Pet names only). No use of y/n, y/e/c etc.**
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Dream felt nervous.
He was usually the optimistic one, always seeing the bright side of things. But tonight, something felt off.
The house was silent. Nightmare had been working late hours recently, leaving Dream to eat dinner alone, but this wasn't loneliness creeping in. This was fear.
He didn’t like being separated from his twin. Not now. Not when everything was so wrong.
Not when he knew he was being watched.
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AKA Dream and Nightmare getting stalked by our two lovable boys, Killer and Cross <3 haven't written a fanfic in years so this might be ass. Also title is inspired by the song with the same name!!
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This fic is discontinued and will not have any more chapters.
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Killer lived his whole life by following 3 crucial rules, what happens when he accidentally breaks all of them?
How does he cope with a world that is slipping away from him as he struggles to keep himself from spiralling?
Can he help everyone or will he fall?