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my heart. (HT!Sans/Reader) by Calibri_1201
Fandoms: Undertale (Video Game), Horrortale - Fandom
12 Jul 2026
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Summary
A Yandere Horrortale Sans x Reader fanfiction. (College AU.)
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After monsters rise from the mountain with the help of a worryingly skinny little girl, they adapt and enter society with relative ease. Obviously there are racist bigots, but for the most part, they are welcomed.
Legal issues get sorted, and monsters are officially allowed the same rights to an education as humans. Mars and Jupiter join with their respective courses set out, and both encounter a peculiar human. Jupiter sees a new friend, and Mars sees an angel. After living in a lawless land for so long, Mars' sense of normal is just skewed enough to let him think what he is doing is fair. It's for his datemate after all. He switches his course to yours, and with the encouragement of his brother, gets rid of his obstacles and competition in (mostly) non-violent ways.You are his heart.
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Sans is named Mars
Papyrus is named Jupiter
Reader is named Protag.--
i absolutely cannot promise regular updates. -
Chainsmoker Frisk (Inspired by Chainsmoker Cat) by Blinleqx
Fandoms: Undertale (Video Game)
12 Jul 2026
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Summary
Undertale!Frisk falls down the mountain with a pack of cigarettes, a broken lighter, and a broken container of mints.
This wouldn’t do.!Frisk is 14! - Parents were smokers/alcoholics, genetics followed through their blood and into Frisk. A family of addicts, will Frisk survive addiction in the underground?
Or will a certain skeleton hook them up?- Language:
- English
- Words:
- 2,138
- Chapters:
- 2/2
- Hits:
- 6
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API (application programming interface) by ElAmanteDeReaper
Fandoms: Undertale (Video Game)
11 Jul 2026
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Summary
Geno es una anomalía en el mundo de Reaper, solidificando su estancia el momento que decidió consumir el fruto de los dioses, recibiendo la oportunidad de poder vivir con una familia y amigos una vez más.
¿Aceptará este nuevo comienzo? ¿O se estancará en el pasado, en su universo destruido?Una API (Interfaz de Programación de Aplicaciones) es un conjunto de reglas y protocolos que permiten que diferentes programas de software puedan comunicarse entre si. Las llaves de API no son seguras en su totalidad, pues cualquier que pueda acceder a estas llaves tendrá acceso total al programa.
- Language:
- Español
- Words:
- 1,392
- Chapters:
- 1/?
- Hits:
- 1
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Summary
Becoming stronger is addicting, intoxicating. In the far past, Chara has wielded that power many times, too many to count.
But that isn't today.Today, Chara lives on the surface. Thanks to Frisk and all of their friends, revived and living a good life, sharing a house with their brother Asriel, just... living. Haunted by the past, but they are managing.
But what would happen if someone triggered that sense of power yet again? Many years down the line, nobody remembers how addicting it is to be in control.
And all it takes...
Is one small misstep...
One short skeleton who couldn't keep his feelings contained. -
A Melancholy "Survival" by EstrellaGoblin
Fandoms: Undertale (Video Game), Undertale AUs - Fandom
12 Jul 2026
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Summary
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The former Guardian of Negativity starts thinking about his home and past. Leaving the thing that now has control over his body to be his only source of comfort as guilt gnaws away at him.As for the creature? Well, corrupted knows not of complex emotions and is doing its best to calm it's host down.
------- Language:
- English
- Words:
- 980
- Chapters:
- 1/1
- Kudos:
- 3
- Hits:
- 9
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Susie goes places she shouldn't by The_Glitch_Error
Fandoms: Deltarune (Video Game), Undertale (Video Game)
12 Jul 2026
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Summary
Susie goes to places she shouldn't and can't find Kris, but she did find a random blue and pink child named Frisk, so yeah
Where is Kris?
Why is a flower trying to kill us?
Why is Toriel evil?
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Summary
A dumping ground for Deltarune pieces that are unfinished, old, or so on. Specific contents and warnings are included in each chapter’s title and/or notes.
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Summary
Yahoo baby’s first fanfic yall should read it its like cool and stuff anyWAYS
Kris and Noelle are gone. No one expected for them to vanish, but then again, that sort of thing is hard to predict. When a secret part of the prophecy is revealed, Susie teams up with an unlikely friend to go back and change how the events of the fun gang’s adventures unfolded. When all hope is lost, the two must call upon a mysterious power to fight back against a great evil. After all, lost things are not always gone.
OR
A girl who refuses to accept fate and a man who knows more than he lets on try to fix the prophecy by going back, undoing the weird route and finally fulfilling the prophecy the right way!
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Through happenstance, an Angel learned the game they were playing was real, and their preparation for its apocalypse was lengthy.
Yet, regardless, the Roaring came. The light faltered. Everyone fell.
An connection was made to an anchor they had forgotten. If the Angel truly dies, all hope will be lost. But, still, the plan remains the same: Understand the world, and so save it. -
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Summary
Doomsday prep has always been necessary in my opinion. If not for your time, then for another's time. So I got married young, to a much older, much richer man, waited a few years for him to die (cancer, so sad), and collected that money like candy at a parade. Then I picked out a nice place for a bunker, and had that thing built in another few years. When Monsters busted out of the mountain nearby, turning some Humans into Monsters, I was only slightly surprised the government's decision was to fucking nuke them all. Now I'm closing the door, and I see people in the distance waving their arms, yelling. I should just close the door, I don't know them, but I don't think it's fair to leave them out to die.
Author's notes, kinda:
Gonna be just Horror, Fell, and Fell/Swap variants.
Characters like Sans, Toriel, Asgore, Frisk, and others are really only mentioned, except Horror Sans.
Papyrus variants are more like different people in this, than variants of the same person.
Also, I don't really like Swapfell Pap (Purple) so sorry, but he might only be there for drama, not for a relationship -
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Summary
You lived a normal life trying to pursue a medical degree to help others, but when you end up in a hospital needing help, a group of skeletons appears, and they are determined to help you. Wait, Skeletons? No, that wasn't right, monsters don't exist.
But they do
For some reason, anytime you try to face the reality of your situation and remember the time before monsters, you suffer from a debilitating headache. Even memories you don't remember living, classes with or about monsters seemed to appear in your memories! Everyone around you swears that monsters have been on the surface for years, and yet, you can hardly remember monsters existing all the years they've been aboveground. You can no longer trust your memories, can you trust these skeletons?
Will you discover the cause of your new memories? And will you discover why the skeletons all seem to be intent on staying by your side?
✌︎■︎♎︎ ⬥︎♓︎●︎●︎ ⍓︎□︎◆︎ ♌︎♏︎ ♋︎♌︎●︎♏︎ ⧫︎□︎ ♒︎♏︎●︎◻︎ ❍︎□︎❒︎♏︎ ⧫︎♒︎♋︎■︎ ⧫︎♒︎♏︎ ⬧︎🙵♏︎●︎♏︎⧫︎□︎■︎⬧︎ ♌︎⍓︎ ⍓︎□︎◆︎❒︎ ⬧︎♓︎♎︎♏︎✍︎
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Summary
Susie knew something was wrong with Kris and Noelle on the day of the festival. She knows she should have listened to her fears too.
Basically a fic centred around Susie during Snowgrave festival, and her having to save Kris and Noelle.
Contains Deltarune Chapter 5 Spoilers
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Who would have thought that an argument between you and your sibling would lead you to meeting monsters. Let alone one of them turning into the love of your life.
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The story of Dreamtale was usually told one of two ways. Either Nightmare gets the 999 apples, or Dream does. Either Dream is left with the only apple remaining, or Nightmare is.
Of course, it varies. But the "apple incident" usually ended with either or.
The sibling that gets the 999 apples corrupts. The sibling that did not protects the only one that remains.
So, theoretically, would it be a good thing if... they were on equal footing? Both twins, getting 500 apples each?
Or would it end in disaster for the entire multiverse they inhabit?
- Language:
- English
- Words:
- 5,088
- Chapters:
- 1/?
- Hits:
- 22
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Petals Falling Down (In The Underground) by ToastandHoney
Fandoms: Deltarune (Video Game), Undertale (Video Game)
11 Jul 2026
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Summary
Alternate Universe Where The Fallen Human Souls Are Based Off Their Deltarune Flower Interpretations
Inspired By; Squiddyinks (Specifically Instagram) GO CHECK OUT HER ART ITS SO PRETTY
Pronouns and Approximate Ages From Oldest To Youngest;
Flowery (He/Him), 16 Years Old
Pink (She/Her), 14 Years Old
Green (They/Them), 13 Years Old
Blue (He/Him), 11 Years Old
Yellow (He/Him), 11 Years Old
Seth (They/Them), 10 Years Old
Orange (She/Her), 8 Years Old
Aqua (She/Her), 7 Years OldFlowery, Pink and Orange are siblings due to their wikis saying that they are 'adoptive siblings'.
Seth and Aqua are siblings cuz it's funny. -
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A child falls into the underground.
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Frisk and Chara have freed the monsters from the Underground, but the cost — paid by humans and monsters alike — has been steep. What blooms after a victory like this is not given; it must be tended. In the wake of their victory, Frisk, Chara, and the Dreemurr family must confront their past and determine what their future will look like as they look to mend the rifts a century of imprisonment and tragedy have created.
Series
- Part 2 of Where the Flowers Grow
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After waking up in a completely new world, Tenna attempts to navigate the world before him. Friends are made, secrets are kept, and romance starts to blossom. It's just a shame he can't see his face.
Series
- Part 6 of Papyrus
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Summary
Different little stories about Frisk and Chara (my two favorite traumatized children)
(I've barely read Undertale fanfics before so this might be OOC or off on the fanon stuff)
- Language:
- English
- Words:
- 396
- Chapters:
- 1/?
- Hits:
- 17
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Summary
Underfell. La règle y est simple : "tue ou crève". La loi du plus fort y est souveraine et ceux qui font preuve de faiblesses sont sacrifié sur son autel.
Mais une nouvelle venue va rejoindre le cœur corrompu de la montagne, s'infiltrer dans les boyaux de l'Underground et retourner la vision de ceux qu'elle y croisera.Elle est un typhon.
Il n'appartient qu'à celui qui la croise de la suivre dans une vie plus palpitante ou de se noyer.
Je dédie cette histoire à ma femme, mon soleil, qui m'a donné l'envie de poster après tout ce temps ♥