Underfell Stories

You're a human that has fallen into Mt. Ebott on the year where all humans dress as monsters...Halloween. So how will the monsters know if you're a human or not?

"How rude, not even gonna ask for a name??" He teased. "Why are you here?" You glowered, raising the whisk. The skeleton scoffed: "Well, glad yo...

Papyrus finds himself curious about the machine Sans has behind their house. When he accidentally activates it, he ends up sending himself to the world of Underfell. Mea...

A girl who has never seen the world outside of the lab sees it for the first time only to fall down into the underground. What will she find down there?

(DISCONTINUED) Heya buckaroozios, i made this 5 years ago man, idk anymore This book will no longer be updated, soon to be deleted eventually when I decide in a few mont...

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

(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...

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...

Sanses included will be...Classic, Swap, Fell, Swapfell, Ink, Error, Dream, Nightmare, Dust, Killer, Lust, Horror, and Fresh. Please be aware that the pronouns used for...

Best ranks: #8 in fanfiction; #1 in undertale; #3 in sans; It was all a dream.....or so you thought.. Edgy: bish how dare u say that was a dreem, it was true af, fite...

Completely female readers unless a request asks different. That's...really about it, enjoy!

Okay so I did wheel decider to help me with y/n love Interest for this book. So I did One Love Interest, Two Love Interest, or All Au sans. And the wheel has chosen All...

Heya! I'm X, and I'm here to write some "x readers!" You can suggest pretty much every AU, and I'll even do some of my own AUs just for fun! Anyways, I hope yo...

Y/N's been traded and sold her entire life. She's learned firsthand that if you don't obey your master, you get hurt. If you force yourself to listen, you live another d...

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...

If you can't tell what this is from the title idk what to tell you... I will do requests and they can be as detailed or as vague as you want. I will do OCs if you want. ...

One clumsy moment and a broken leg are all it takes to leave you at the mercy of the very edgy and very hostile monsters of the underground. Thanks to your knowledge as...

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...

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'...

What if someone died and became the tree of feelings from dreamtale? Well things won't stay the same, that's for sure. (Different everything etc, different personalities...