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1. A Soul’s Descent by Ren_is_Random

   Fandoms: Undertale, Underfell - Fandom  

   • Mature
   • Graphic Depictions Of Violence, Creator Chose Not To Use Archive Warnings
   • Other
   • Work in Progress

   16 Jul 2025

   Tags

   • Graphic Depictions Of Violence
   • Creator Chose Not To Use Archive Warnings
   • Frisk & Sans
   • Frisk/suffering
   • Frisk (Undertale)
   • Sans (Undertale)
   • Sans (Underfell)
   • Flowey (Underfell)
   • Toriel (Underfell)
   • Papyrus (Underfell)
   • Undyne (Underfell)
   • Angst
   • Hurt/Comfort
   • Suffering
   • Friendship
   • Child Frisk
   • Female Frisk
   • Big Brother Sans
   • sans protecc frisk
   • classic
   • Red - Freeform
   • Undertale AU
   • universe hopping
   • but only at the beginning
   • Frisk did a bad
   • but she’s trying to make it right
   • some tags won’t be listed
   • ’cause tags with spoilers need to die in a fire
   • Tags confuse me
   • brought over from quotev
   • Post-Traumatic Stress Disorder - PTSD
   • Depression
   • Blood and Gore
   • Swearing
   • Self-Hatred
   • kustard - Freeform
   • Kinda
   • but not really
   • Frisk Needs A Hug
   • A Soul’s Descent
   • previously know as Soulfell
   • Frans - Freeform
   • kind of?
   • but not really again

   Summary

   Frisk absorbs Sans' soul after an unintentional genocide run. In her grief, she resets to try to fix it and make everything right. However, things don't go as planned and she ends up in a violent version of the Underground. With Sans stuck in her head, she now has his magic to help them survive and escape. But Frisk is committed to sparing. It will be difficult to spare when everyone here wants to kill her. What will she and Sans do?

   Language:

   English

   Words:

   106,467

   Chapters:

   32/?

   Comments:

   138

   Kudos:

   471

   Bookmarks:

   111

   Hits:

   15,794