Underfell Stories

trigger warnings will be placed at the beginning of each chapter! this story will contain mature content, be warned before reading.

[3rd book] So it's yandere Undertale One shots because I can. Also because some characters just kinda need to be more recognize. Slow updates? Or it will just Update at random. Also there might be some errors so sorry about that. Started - 4/9/23 Ended - 5/31/24 I don't own Undertale or the Characters! Not the Cover I just edited it!

Underfell is a dark world with the major rule of kill or be killed. Even though children are suppose to be secluded from this rule, that doesn't stop monsters from hurting children. Undyne is a monster who lives in Waterfall. Under the care of Gerson. One day while out on a walk the fish monster stumbles across a baby. Though it wasn't any monster. It was a small little baby skeleton. (the cover is only temporary, until I'm able to make a cover for the story)

Y/N never thought her dreams meant anything. Not until they started pulling her somewhere new, somewhere dangerous, vivid, and impossibly real. Every night brings her back to the same mysterious figure. Every morning she feels less like herself. As her dreamworld grows clearer and her real life falls apart, one thing becomes certain: Someone - or something - is waiting for her on the other side. And meeting him changes everything. ✨️ Coverart by mini-shrimp14 on Tumblr

Juste un Red!sans x reader

Ink has made a new au... Being tale where every one of the aus for a character is in one, for you though. You're sans, but What happens when ink finally lets you meet the other true sans aus which you where made from? And what new power do you have, that the other sans don't, and how will it affect you? Read to find out! Future lemon warning!!!

Your world. No. Your universe was about to be destroyed. As much as you didn't want to leave, you couldn't let him take over. So you did the only thing you could think of. You activated an ancient spell which prevents him from ever coming back to your universe. The bad thing? You can't go back to your universe either. Suddenly you awake in snow and find yourself trapped Underground, a place inhabited by kind monsters, skeleton brothers, and a young kid who can reset time. As you grapple with your new reality, you realize he is here too, endangering the beings you have grown fond of. Now, in this unfamiliar world, you must confront the consequences of your actions. Can you protect your newfound companions from the coming shadows or will they fall victim to the evil you inadvertently unleashed?

Sans and Papyrus were just trying to have dinner. They didn't expect things to blow up (literally). Now they have a destroyed machine and a young babybone that they suspect as a Shifter. Where did they come from? And who's life privilege they need to remove? Because this babybone is clearly been abused or worse. Now then, where's that parenting books Sans been storing since Papyrus a babybones, he's definitely need a review if they want to keep the kid from getting killed. At least the kid's adorable...

Kyra falls into the underground, while there she finds that her connection to the monster realm goes deeper then she thought. Cover by @rykosen Undertale belongs to Toby Fox

Long ago, two races ruled the Earth: HUMANS and MONSTERS. One day, war broke out between the two races. After a long battle, the humans... wait no, the monsters were victorious. They sealed the humans underground with a magic spell. The humans were the ones stuck in the underground but there was a special human, (Y/N) (L/N). Like any other human there, she lived a normal life, making mistakes, having her good and bad moments, and all of that. Her universe was different from the other alternate universes, but it still had its similarities. The Guardian of the AUs, Ink, had never seen her universe until Dream caught noticed of the universe. And with that, Ink, Dream, and fellow other Sanses went to venture on into her universe.... (Remake; V.2)

" what am i supposed to do? " | Underfell AU | ©︎ 2018

Hi! This is a random idea I came up with, and in it, I'll be listing every undertale au I know of, and (at least) every main character within them. In my point of view, of course. If anyone wants to share their views on any of them then fine by me, also tell me if there are any I missed and should check out. Also note that I do try to learn about them, but there are many different views on each, so refer to earlier. I may add some AUs I have not heard of, or don't exist (which I highly doubt) and have created by myself. Cover art: http://img0.joyreactor.cc/pics/post/Undertale-%D1%84%D1%8D%D0%BD%D0%B4%D0%BE%D0%BC%D1%8B-Frisk-Undertale-%D0%BF%D0%B5%D1%80%D1%81%D0%BE%D0%BD%D0%B0%D0%B6%D0%B8-2651184.png

[Y/N] is a long standing member of the Royal Guard, serving directly under the Great and Terrible Papyrus. They would do absolutely anything to protect their Captain and make him happy, but can he even see them past himself? To make things easier, in this fic you are a owl monster.

Blueberry/ swap sans has been trapped in the void for awhile. It's time for him to get out of that white hell hole and back home, well not exactly home but close enough.

Cupcake/Fell Goth, lived a hard life in UnderFell. She(Yes I'm making Fell Goth a 'she') and her parents fight quite alot. She one day meets a certain skeleton while she was grocery shopping. She yelled at him. He took her with him. They bond over the time. He's cruel but she likes him but knows that in UnderFell, you can't love someone. Will Cupcake be able to tell her special someone how she feels? Pudding/Fell Palette, lived with his father Ink after his mother Dream passed away. He loves murder and gives no mercy. While wandering around ina store he meets someone unique. She didn't cower in fear when she saw him. She even yelled at him. They bond over the time. She's rude but he likes her but knows that in UnderFell, you can't love someone. Will Pudding be able to tell his special someone how he feels? Follow them in violence, betrayal, heartbreak and cruelty in Do You Even Love Me?

THIRD TIME IS THE CHARM! [Highest ranking #98 in fanfic] NO IMAGES R MINE

This is the swapfell AU. It's a mashup of underfell and Underswap. So this is going to be fun! I do not own Swapfell and this is not an official book. Enjoy this book!!!!

Fell has a big secret. the back of his closest is filled with red, frilly dresses and he seems to flinch when someone uses male pronouns towards him. Fell is transgender. He secretly calls himself 'Cherry' in secret. He has the biggest crush ever on classic Sans, and is shocked to one day find,that his crush,loves him back. A little to much.

When Sans learns that Red is cutting himself he chooses to run away instead of talking to Red. Can Sans save this relationship? Or is it too late?

As a short skeleton slept in the snow, he met another version of himself just... edgier, will they become friends, enemies, or more? Read to find out. This may have lemon or something in it, so be careful when you read, also will post chapters when I can. Also, may not be canon so- Sans Belongs to Toby Fox Fell/Red Sans belongs to Fella/Vic (I think, that's what google is telling me.)