Underswap Stories

Somehow...I've become a sans...and not just any sans.. I'm classic!? What the flip is going on!? Wait why are different sans and papyrus's showing up at my home? I didn'...

Blue is sick of being treated like a child by his friends and family. He shoves down his negativity in order to stay 'happy' like they want though. Nightmare has had eno...

[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...

You were always put in second place due to your sister being favored over you. No matter what you did it always seemed that you both were competing against each other. Y...

What will happen when you've grown up with the king of nightmares. Will he let you go, well, we will see The mentioned au's dont belong to me, they belong to their respe...

what if someone in our world becomes US!sans also known as blueberry?

You're Frisk's friend, who jumped down the Underground. Not wanting to leave him alone, you jumped after him. After a lot of pacifist routes and resets, you woke up in a...

What if two brothers somehow end up in their own story as the sans and papyrus that they made? They called the story starfell, mostly because everyone in the story is li...

Yep,this is what my life has come to -~- *sigh*

"There IS worse fate than death" The cover isn't mine. Just a few warnings: -boyxboy -girlxgirl(maybe?) -blood -su¡cide(kinda) -death

You are locked below ground where nobody can find you. Chained to a wooden post in a dark, cold room. You are left with no memory and pain all over. You are left there f...

You fall after being pushed of by the two people you thought that loved you, you thought that you would die. You wanted to die but not like this, ask you hit the floor e...

I wanted to try it out do why not?

what if someone from our world died and was reincarnated as atomic!sans/wyvern? please understand that the au of 'atomictale' was made by me and i dont mind if anyone us...

what would you do if all of a sudden some small skeletons appeared out of nowhere one night and we're so small and helpless you couldn't say no to. So your living with s...

You are a introvert who loves undertale and multiverse and loves to play video games and listin to music. What will happen if one day you meet the skele-bros of differ...

What happens when two Multiverses collide? When alternate versions of each other meet in the blank space between Universes? What happens when they try to leave? True neg...

What if someone is reborn as Error? What if they aren't so bad? What if they're suffering in silence and keeping their job a secret for fear of hate? How will Ink react...

What if someone died and was reborn in an undertale au as a siren? And not just any kind of siren, but a sans, a skeleton siren. They can change back between full skelet...

Rain is upon first glance is a normal, teenage human. What most people don't realize is that they suffer from extreme depression and is a victim of abuse, all the while...