Underswap Stories

[Prolong] My name is (Y/N). I have experienced many resets, so many I have lost count. The only people who remember are Sans, Flowey, and me. The monsters down here are...

It was a beautiful day, a Friday, and two writers with too much time and way too much energy plunked down Error and Blue into a new Multiverse. Dreamswap, to be precise...

What if someone from our world became error and didn't destroy au's and left that for nightmare and his gang and claims au's? ( different things including personalities

(As far as I know, no one has made a story about naturetale like this so..and the only reason why I writing one like this is because of fatal error part 5? Or part 4, go...

Note to self: Never make jokes about getting reincarnated into a video game character because it'll actually happen. Welp too late to go back now, considering I'm alread...

Yeah sorry gained an idea on if someone became swap Gaster Also they may be apathetic or just confused on their feelings and MAYBE Autistic, I may be a bit wrong on ap...

Right before being completely destroyed, the machine pulls through a lone papyrus called Wick. Struggling with memory loss, trauma and disability, Wick learns to find ho...

This will be fuuuuuuun

!! Long Chapters !! 1000-4000 words each! **This book will be continued by another person so check the A/n at the end of the book to go to their continuation of this!** ...

The Multiverse is vast, expanding continuously as more alternate dimensions are being created. Each world possesses it's own unique laws, stories and inhabitants. This w...

Y/n was and/or is a very sweet child, unfortunately for them they weren't treated very well by their mother or father, Y/n was abused and didn't have anyone. Fortunately...

Nightmare found a young child a long time ago. When they fell into a coma it sent him over the edge. several hundred years later the child wakes up in a castle of darkne...

What if someone from our world was transported into momma Cq as nightmare? What if a bit later after being nightmare for a while, he finds the momma Cq version of nughtm...

After Blue's "kidnapping" Blue is returned with an Error doll. Everyone thinks it's creepy, but what happens if it's taken away or destroyed? Then there's a wh...

Blueberry - Sans of Underswap. But is he so different from Undertale Sans? Find out as we view Blueberry Sans' life in the Underground. I don't know what rating is used...

What if..someone from our world was reborn as fellswap sans? But an accident when he was young leads to becoming blind for a long time and papyrus feels guilty about not...

I found this pictures on deviantart,pinterest,google and Frans Amino

This story takes place after the player vanishes from their fight with the bad time trio aka Sans, Shift, Stretch. The three got stuck there for a very long time until a...

I was reborn as sans from my own made up au. How did that happen? I have no idea. Luckily I was still a kid so I didn't have to act like how I made sans to act like but...

What if someone became papyrus from underswap? What if they gave their brother more freedom? What if they were the one that error kidnapped instead of sans? (Things wil...