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1. (DISCONTINUED) An Unhealthy Obsession by Cake_Ekac

   Fandoms: Undertale (Video Game)  

   • Explicit
   • Creator Chose Not To Use Archive Warnings
   • M/M
   • Complete Work

   13 Nov 2025

   Tags

   • Creator Chose Not To Use Archive Warnings
   • Sans/Sans (Undertale)
   • Crossmare
   • Driller - Relationship
   • Sans (Undertale)
   • Sans Ensemble (Undertale)
   • dreamtale sans - Character
   • Nightmare Sans
   • Cross sans
   • Killer Sans - Character
   • Stalking
   • Possessive Behavior
   • Passive Dreamtale Nightmare Sans (Undertale)
   • Dreamtale Nightmare Sans/XTale Sans | Cross (Undertale)
   • Dreamtale Sans | Dream/Killer Sans (Undertale)
   • Jealousy
   • Killer being a creep
   • Cross is also a creep but he tries to convince himself he isn't
   • Killer is a big romantic
   • Even while stalking
   • Cross's words and thoughts are two different people
   • Dream's lowkey into being stalked
   • Only when he finds out it's Killer tho
   • Nightmare not so much
   • There's a scene where Cross kisses Nightmare without consent
   • Ecto-Genitalia (Undertale)
   • Ecto-Penis (Undertale)
   • Ecto-Tongue (Undertale)
   • Ecto-Vagina (Undertale)
   • Possessive Sex
   • Kinda dubcon?

   Summary

   Dream felt nervous.

   He was usually the optimistic one, always seeing the bright side of things. But tonight, something felt off.

   The house was silent. Nightmare had been working late hours recently, leaving Dream to eat dinner alone, but this wasn't loneliness creeping in. This was fear.

   He didn’t like being separated from his twin. Not now. Not when everything was so wrong.

   Not when he knew he was being watched.

   ________________________

   AKA Dream and Nightmare getting stalked by our two lovable boys, Killer and Cross <3 haven't written a fanfic in years so this might be ass. Also title is inspired by the song with the same name!!

   ___

   This fic is discontinued and will not have any more chapters.

   Language:

   English

   Words:

   50,306

   Chapters:

   11/11

   Comments:

   99

   Kudos:

   260

   Bookmarks:

   31

   Hits:

   4,937