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1. Rules of Survival by Dunuthin_31

   Fandoms: MafiaFell (Undertale)  

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

   23 Oct 2025

   Tags

   • Graphic Depictions Of Violence
   • Major Character Death
   • Rape/Non-Con
   • Mafiafell Gaster/Reader - Relationship
   • Gaster/Reader
   • W. D. Gaster/Reader
   • W. D. Gaster
   • mafiafell sans
   • mafiafell papyrus
   • Jack (OC)
   • Larry (OC)
   • Muffet (Underfell)
   • Reader
   • Don Romano (OC)
   • Gaster is a bad guy
   • Eventual Smut
   • Porn With Plot
   • Some stalking
   • Other Additional Tags to Be Added
   • Porn with a lot of Plot
   • not slow burn though
   • Human/Monster Romance
   • mafia
   • Mobsters
   • Set in separate universe than Sooner or Later
   • Reader Is Not Frisk
   • Reader Is Not Chara (Undertale)
   • Reader may not be named?
   • I'll add later
   • Past Abuse
   • Guns
   • Minor Character Death
   • like right away
   • IMMEDIATELY
   • Major Character Death (eventually)
   • Reader is probably around 25-30
   • Trying not to make that super specific though
   • Dual POV?
   • some sibling bickering to come
   • The sibling bickering has arrived

   Summary

   This is my first fic, so please be gentle.

   You live in a city in the 1920s, and it is overrun with mobsters. Because of this, you're extremely cautious and like to stay informed about what is happening around you, but you come across a man with quite the... unique mindset for a mobster. You don't trust him at first, but he'll win you over eventually.
   He will make sure of it.

   This is short for now; I will be adding more later, as I'm currently sleep-deprived.

   Language:

   English

   Words:

   1,790

   Chapters:

   2/?

   Comments:

   3

   Kudos:

   13

   Bookmarks:

   2

   Hits:

   192