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1. The Priestess and the Soul Guardians by FireflyKisses

   Fandoms: Undertale, Underfell - Fandom, underswap, Fushigi Yuugi  

   • Mature
   • Graphic Depictions Of Violence, Major Character Death, Rape/Non-Con
   • F/M, Multi
   • Work in Progress

   30 Jan 2026

   Tags

   • Graphic Depictions Of Violence
   • Major Character Death
   • Rape/Non-Con
   • skelebros x reader
   • Sans x reader - Relationship
   • Sans
   • Papyrus
   • Red
   • Edge
   • blueberry - Character
   • Stretch - Character
   • UF Sans - Character
   • UF Papyrus - Character
   • US sans
   • US Papyrus
   • Toriel
   • Gerson (Undertale)
   • UF grillby
   • Reader Insert
   • reader becomes a priestess
   • Timelines
   • Alternate Universe
   • Alternate Universe - Canon Divergence
   • soul gathering
   • Fushigi Yugi but Undertale
   • gathering the guardians
   • summon the beast god
   • Suicide Attempt
   • Talk of Suicide
   • soul of determination
   • Reader Is Not Frisk
   • Reader Is Not Chara
   • reader is female
   • magical girl
   • Prophecy
   • Oracles
   • reader is an adult
   • after a nuetral run
   • and a genocide run
   • and a mercy run
   • too many resets
   • Sans has suffred
   • Papyrus is Awesome
   • civil war in the underground
   • Asgores dead
   • so is alphys
   • Undynes lost it but is not evil
   • Shojo - Freeform
   • talk of self harm
   • non-con marking
   • Murder
   • Death
   • Impaling
   • soul mates
   • soul bonds
   • Marking
   • Lots of Angst
   • dubcon
   • Emotional Manipulation
   • Personal Growth
   • learning to love yourself
   • learning the will to live
   • Empathetic Reader
   • Okay mature rating update
   • Dubious Consent
   • Polyamory
   • Graphic Descriptions of Sex
   • Intimacy
   • Fingering
   • A bit meta

   Summary

   A human girl thinks she's ending her life when she throws herself down a crack on Mt Ebott but is found and healed by the skeleton brothers. It soon becomes clear that she might be a much anticipated priestess who has the power to summon the beast god that can free monsters from the underground. She must travel through timelines and alternate universes to find her guardians, skeleton monsters with strong souls who will aid her in her quest to summon the Beast God and make her dreams come true.

   But will it turn out like the prophesies say? Can there be a happy ending?

   Fushigi Yuugi/Undertale hybrid fic. This story is shojo.

   Language:

   English

   Words:

   399,622

   Chapters:

   31/?

   Comments:

   947

   Kudos:

   1,282

   Bookmarks:

   258

   Hits:

   33,452