Plenty of horror mods out there, looking for a mod that makes NPCs react appropriately to the horrific conditions being imposed on them (by us.)
I've thought of a few versions based on the most popular zombie and such mods
1. for everybody everywhere
-currently, the Corpse Fairy sneaks in between your loading screens and takes all the corpses. NPCs should use RIP and animations to drag corpses away from places they care about and dispose of them for the player's immersive pleasure.
-RIP: bury dead NPCs -- different burial methods used depending on relationship to NPC: neutral = just get rid of it, friendly = proper disposal, enemy = f*** with it/display it
2. for living dead apocalypse
-NPCs will destroy the head of every dead body they find that still has one...they've figured that out
-plenty of killmoves/animations available to get this done Gears of War-style (Knockout Framework has 3 perfect ones for removing the head from a ragdoll NPC, and I would recommend this mod)
***3. for Ash vs Evil Dead apocalypse - Separate mod idea on its own, got inspiration after after rewatching the show and thinking of 1. and 2.
-starts by picking up and reading from the Necronomicon, causing "Deadites" (demons) to become aware of you and the book's current location
-Deadites are buffed versions of the NPCs whose corpse they are possessing (faster, stronger, tougher, stealthier, melee only for some reason)
-Deadites do not want NPCs to know about them, they will pick a corpse with no witnesses if available, if not they will "play dead" until there are no witnesses (including turned backs) before getting up
-Deadites disguise as the NPC (whose body they are using) was before death, follow you from a long distance and only show "corpse face" when there are no witnesses and they think they can kill you or one of your followers, or if you attack them while they are disguised (think: LEGENDARY ENEMY MUTATED)
-if discovered by NPCs while "corpse faced" they will turn their attention to killing witness NPCs (and do a great job) in order to keep their secret
-everyone killed by a Deadite will come back as a Deadite, following all the same rules after just a few minutes of being dead - know when it's time to take out your chainsaw (or chainsaw hand)
-every dead NPC is a possible Deadite target, ideal to play with No Essential NPCs so that if you kill Preston, then find in a month that he has a new settlement for you to help, it's time to take out the Chainsaw(hand)
-KILLING DEADITES: you can't "kill" them, you can use the Kandarian Dagger to "exorcize" them, otherwise you can only use your guns (and Chainsaw Hand) to break them into small, harmless pieces as best you can
-Killing supposedly innocent NPCs is a CRIME!!! So is dismembering bodies for no reason!!! Deadites "aren't real" and that's not an explanation that Diamond City Security will spend any time listening to...
-NPCs discovering a dead body in an enclosed room with you will assume YOU DID IT!! (you kinda did tho) - deal with the increasing legal and societal consequences of being a supposed serial killer and dismemberer!! (jail, bounties on your head, wastelanders talking s***, bad prices with vendors)
-on the other hand, anyone who you SAVE from Deadites will understand what's really going on and become available to be your Follower!!! (Don't recruit them if you care about them...they're gonna die, just take what you want from their inventory and move on)
-Difficulty from 1-5 = how many Deadites can be active at once