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1. A Killer in the Night by An4logHorror

   Fandoms: Undertale (Video Game)  

   • Mature
   • Creator Chose Not To Use Archive Warnings
   • Other
   • Work in Progress

   26 Dec 2025

   Tags

   • Creator Chose Not To Use Archive Warnings
   • Sans (Undertale)/Reader
   • Horror Sans/Reader
   • Horror AU/Reader
   • horror sans
   • Horrotale Sans
   • Sans (Undertale)
   • Reader
   • Horror Sans AU
   • Serial Killers
   • Stalking
   • possible cannibalism
   • Horror's name is Sanguine
   • genderneutral reader
   • AFAB | Assigned Female at Birth Reader-Insert
   • Sanguine is stalking the reader
   • But doesn't intend to hurt them
   • Developing Relationship
   • anxious meltdowns
   • Panic Attacks
   • reader is an overworked office worker
   • Alternate Universe - Undertale Multiverse | UTMV (Undertale)
   • Horrortale Sans (Undertale)
   • Alternate Universe - Horrortale (Undertale)
   • Unhealthy Relationships
   • Small outer cameo in chap 2
   • Outer has feelings for the reader
   • They are not reciprocated
   • more tags tba

   Summary

   You have gained a problem over the last few months, but it has only recently become a problem, as a certain skeleton in your town has grown ... interest for you.

   Language:

   English

   Words:

   3,834

   Chapters:

   2/?

   Comments:

   8

   Kudos:

   37

   Bookmarks:

   7

   Hits:

   348