Underswap Stories

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...

Humanity is divided over one thing---the Monsters' reappearance. Some believe that they should stay aboveground, and others think that they should be sent back to where...

Hi guys! First of all I should mention that the story pic isn't mine and of course Fellswap belongs to its original creator. A young hiker, Y/N gets lost and accidental...

You were a kind human who has a brother named Frisk. You and Frisk always get along until both of you climbed up a mountain. very curious if the legend was true or not...

(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...

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...

(ᴠᴀʀɪᴏᴜs sᴀɴs ᴀɴᴅ ᴘᴀᴘʏʀᴜs ᴀᴜs x ʀᴇᴀᴅᴇʀ) ||ᴀɴᴅ ᴛʜᴇɴ ɪ ɢᴏ ᴀɴᴅ sᴘᴏɪʟ ɪᴛ ᴀʟʟ ʙʏ sᴀʏɪɴɢ sᴏᴍᴇᴛʜɪɴɢ sᴛᴜᴘɪᴅ ʟɪᴋᴇ "ɪ ʟᴏᴠᴇ ʏᴏᴜ."|| Life was merciful enough to grace you...

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...

A picture perfect family hides the fact that your life is filled with manipulation and abuse. When you move away after high school, you encounter more than one skeleton...

He knows he'll be dooming them if he falls, but he's tired, his body is breaking apart, held together on a higher being's whim only. He wonders if there'll be another to...

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...

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

So harem book of Charas and Frisks x male reader but real description is below this. The only one of his person in all universes is part of Undertale with an OP powers b...

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...

Bitty! US pap x reader x Bitty! US sans Our two little bitties have been through a lot, so what happens when they meet a human that's hurting just as much as they are...

...

When made by his father, the god of death, he didn't know his purpose. All he could do was kill things on accident...he didn't mean to kill them, he just wanted a friend...

Sans and Papyrus were your best friends until randomly they just cut off all contact with you. This went for everyone else in your life so it didn't really hurt that muc...

Y/n L/n. A special human with a special SOUL. Yes, her Soul Trait is something new. But other than her SOUL trait she has another secret. One day, while she was at the...

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'...