undertumfan fiction

Fandom · 7 works

5 undertum stories are open to everyone here, 80% of them complete. The average one runs about 18,600 words. Read any of them in your browser, save it as an EPUB, or listen to it.

Works

Some results are potentially explicit

Undertale (Video Game)+1

Sans' Sin Quest

by Sans Sin Quest (Aeonox)

“Uh, since you’re gathering up magic to break the barrier,” He replied, feeling pressure under Sans’ glare. “Whenever you started doing that though, I don’t know.” What? Sans chuckled and leaned back, looking at Matthew and Sal’s faces to read something more out of the other two.“c'mon, who’s the comedian here? heh. don’t quit your day job there, pal.”The three of them looked on in a cocktail of concern and confusion, entirely serious. Sans sat there beside himself, eyelights disappearing into darkness as realization dawned. They really believed he was going to break the barrier by stuffing his face?***************A fic where monsters learn weight acceptance, deal with shamers, anxieties, and weird obstacles, and maybe... just maybe... they can all work together to make a happy ending afterall.

Teen 87k words 12 / ? ch In progress 309 kudos

AND Fat Appreciation · Anxiety · But also Fluff! · Content warnings are posted at the beginning of each chapter!· +20 more

Undertale (Video Game)+1

Big Mistake

by Sepulchral_Sentience (orphan_account)

By the power of science, Gaster explores the processing of monster magic- himself as the test subject. How wise.

Teen 1.8k words 1 ch Complete 88 kudos

Belly Kink · Experimentation · Gaster is Not a Skeleton · Instant Weight Gain· +4 more

Undertale (Video Game)+1

One Heated Baker

by Sepulchral_Sentience (orphan_account)

Grillby bites off more than he can chew when he visits a certain spider's bakery to satisfy his monthly charge of magic.

Teen 2.8k words 1 ch Complete 78 kudos

Bondage · Feeding Kink · Force-Feeding · Instant Weight Gain· +2 more