Oh it's quite simple really
Afton and his buddy oh chum ol pal Henry have this restaurant called Freddy's pizza emplorium where Afton kills some kiddens and covers it up. One of them was Henry's daughter who comes back and wakes up the other kids from their nap and now they're furries who roam the halls of freddys 12 step program at night. Afton gets a ghost fetish and starts experimenting on how to become immortal or bring his dead children back or something and makes child killing bots. Those things start having existential crisis and decide to become otherkin humans and kill and wear his son Micheal. Sad for him his innards are too stanky for them and they decide to leave and he throws them up like a bad hangover. He becomes immortal decides from then on he will work a shitty 9-5 night job at Freddys diddling kids funhouse for the rest of his life!Way before this one of his sons jimmy John is being a fucking pussy and won't go to freddys child eating friendship palace cause he's scared of robot animals so his chad brother try's to help him by committing fratricide and shoving him up golden freddys uncles buttchecks where his head comes clean off. Now jimmy has to battle is fears IN HELL. Speaking of which that's where Afton is now. How did he get there you may ask? Well after taking a hike back to freddys gay mascara shop he notices that the robots are stanky and decides to chop em up to remove the stank. The children get mad after their 1000 dollar fursuits get ruined and chase Afton into a back room where he must put on his secret fur suit to show that he is they. Sadly the cum stains left inside his suit have evolved into living beings and eat him alive and he promptly "dies". Plot twist he didn't die and now he's a furry roaming around Freddys horror closet but it's short lived and he burns alive. Plot twist he's not dead, still alive but now he makes his way to the new and approves Freddys Pizza place Not a trap! Turns out all his friends are here including Micheal, The poopet, baby, his child murderbots, and Henry and they throw him a surprise party! Sadly he sucks at blowing out candles and lights himself on fire again and "dies". Now he's in hell and still working at Freddys fire cafe BBQ where golden Freddy tortures him FOREVER. JK he's alive again somehow but now a ghost computer virus and now he haunts Freddys Vr and chill and decides to start a cult and stealomg bodies and junk.
And that's the pretty simple plot of FNAF or at least what's off the top of my head.
