Is this just an affinity algorithm of some sort? I was playing around making something like this, it really adds a ton of depth to a game, quickly.
My system worked based on dialogue choices made by the player, positive dialogue options would add to a variable called reputation, and negative options would subtract. 0 was baseline affinity where the NPC didnt have any feelings towards the player, and I think +3/-3 was where like/dislike began, and +7/-7 was where love/hatred began. I wanted to expand the system and make more things impact affinity (doing quests, random violence, interactions with "friends" of that npc, etc) but never got around to it.
I always loved systems like that, it adds so much more immersion, and frankly, is not super hard to integrate if done at a basic level like how I was describing.
Good luck with the project, Ryan, sounds cool!