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1. One last promise by Myfanwi

   Fandoms: Undertale (Video Game)  

   • Mature
   • Graphic Depictions Of Violence
   • F/F, Gen
   • Work in Progress

   07 Jan 2026

   Tags

   • Graphic Depictions Of Violence
   • Alphys/Undyne (Undertale)
   • Frisk (Undertale)
   • Sans (Undertale)
   • Toriel (Undertale)
   • Asgore Dreemurr
   • Papyrus (Undertale)
   • Undyne (Undertale)
   • Alphys (Undertale)
   • Flowey (Undertale)
   • Asriel Dreemurr
   • Mettaton (Undertale)
   • Post-Undertale Pacifist Route
   • Sans Partially Remembers Resets (Undertale)
   • Sans (Undertale) Needs a Hug
   • Sans is Having a Bad Time (Undertale)
   • Sans is sick
   • Papyrus (Undertale) Knows More Than He Lets On
   • Papyrus (Undertale) Remembers Resets
   • Papyrus (Undertale) Needs a Hug
   • Younger Brother Papyrus (Undertale)
   • Papyrus is the Best (Undertale)
   • Established Alphys/Undyne (Undertale)
   • Parent Toriel (Undertale)
   • Good Parent Toriel (Undertale)
   • Nonbinary Frisk (Undertale)
   • Nonbinary Chara & Frisk (Undertale)
   • Frisk (Undertale) Needs a Hug
   • Gender-Neutral Frisk (Undertale)
   • Teenage Frisk (Undertale)
   • Flowey Has Issues (Undertale)
   • Flowey Remembers Resets (Undertale)
   • Post-Pacifist ending goes wrong
   • War
   • Sickness
   • Humans don't like monsters
   • Character Death
   • Angst
   • Angst and Hurt/Comfort
   • Lies

   Summary

   It has been five years since monsterkind left Mount Ebott with the help of Frisk. Now a teenager, that’s six months they had been living far from their people with Toriel, who got hired as the first teacher for humans and monsters. Frisk lives that forced exile badly, but summer vacations are close enough to go back to New New Home and see all those they left behind.

   Soon enough, Frisk realizes something is wrong with Sans. Despite the forced smiles, the skeleton is suffering in silence. Worried, Frisk decides to investigate. Is he still mad for all these timelines they did something irredeemable, or is it something deeper?

   One thing is for sure, those vacations won’t be like the others.

   Language:

   English

   Words:

   3,661

   Chapters:

   1/35

   Comments:

   4

   Kudos:

   11

   Bookmarks:

   1

   Hits:

   143