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1. The Skeletons’ Castle by Ambrioletteels

   Fandoms: Undertale (Video Game)  

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

   20 May 2025

   Tags

   • Graphic Depictions Of Violence
   • Rape/Non-Con
   • Major Character Death
   • Sans (Undertale)/Reader
   • Papyrus (Undertale)/Reader
   • Sans (Horrortale)/Reader
   • Papyrus (Horrortale)/Reader
   • Sans (Underswap)/Reader
   • Papyrus (Underswap)/Reader
   • Sans (Swapfell)/Reader
   • Papyrus (Swapfell)/Reader
   • Sans (Underfell)/Reader
   • Papyrus (underfell)/reader
   • Killer!Sans/Reader
   • Nightmare!Sans/Reader
   • Dust!/Sans/Reader
   • Sans (Undertale)
   • Papyrus (Undertale)
   • Horror (Horrortale)
   • Tatters (Horrortale)
   • Blueberry (Underswap)
   • Stretch (UnderSwap)
   • Blackberry (Swapfell)
   • Mutt (Swapfell)
   • Red (Underfell)
   • Edge (Underfell)
   • Killer!Sans - Character
   • Nightmare!sans
   • Dust!Sans - Character
   • Error!Sans
   • Reader-Insert
   • Yandere Skeletons
   • Female Reader
   • Survival Horror
   • Angst and Fluff and Smut
   • Runaway Main Character
   • Threats of Rape/Non-Con
   • Ecto-Tongue (Undertale)
   • Ecto-Penis (Undertale)
   • Soul Sex
   • Soul Bond
   • Blood and Violence
   • Hurt/Comfort
   • Masturbation
   • Body Worship
   • Cunnilingus
   • Blowjobs
   • Anal Sex
   • lots of eventual sex
   • Alternate Universe- Dating Sim
   • AFAB reader- Freeform
   • Multiple Endings
   • Obsessive Behavior
   • romance/thriller
   • Psychological Horror
   • Character Death
   • Unreliable Narrator
   • Loss of Humanity
   • Identity Crisis
   • Body Horror
   • Supernatural Elements
   • Shamless Shipping
   • Flirting for Survival
   • Unlocking Achievements (And Trauma)
   • NPCs are getting too self aware
   • Player choices have consequences
   • Ecto-Genitalia (Undertale)
   • Obsessive Skeletons Hot/emotionally unstable/silly guys
   • Reader has purple soul
   • Reader isn't actually ugly
   • Roleplay
   • Reader fails at surviving often
   • Mating Cycles/In Heat
   • Mating Rituals
   • Slight Monster A/B/O dynamics
   • Skeleton Reader (Undertale)
   • Eventual Skeleton Reader Transformation

   Summary

   Reader is an exhausted retail worker with nothing in life to look forward to but finishing her shifts daily, coming home, and playing her new RPG VR dating sims game called The Skeletons’ Castle.

   She knew she was probably weird for preferring a monster romance simulator over the ones with the usual ‘hot’ anime male options, but it had just the perfect amount of horror and mature themes she was looking for.

   One particularly hard day in her life, reader turns to her game to escape, this time restarting a save file after a particularly brutal ending that leaves her disappointed. What she doesn’t realize, is this is her last and final play through, because she gets transported into the game as a random side character, not even as the main character! And now she can’t exit!

   How will she survive this intense game, or rather, her new reality?
   ON HIATUS UNTIL 2026*

   Language:

   English

   Words:

   68,157

   Chapters:

   13/?

   Comments:

   163

   Kudos:

   414

   Bookmarks:

   100

   Hits:

   9,913