Long story short: The red pill is the entire fnaf lore.
Double tap to edit Nothing In the 1970s, two friends both named William Afton, and Henry Emily start a business called, “Fredbears family diner”. Business skyrockets in the 1980s,with some major advancements. However,in a summer of 1983, one of Williams sons has a birthday there. Micheal Afton, his older brother, thought it would be a funny prank to stuff him inside Fredbears mouth,only leading to a spring lock failure,and causing Evan (The victim.) to die. William was enraged when this happened. This closed down,so they open up a new one, Sister location. On the first day of opening day, Williams daughter, Elizabeth Afton, believes that the animatronic Circus Baby has ice cream. She wants ice cream, so she goes up to her, only to get scooped inside the animatronic. It is also believed that Williams wife is Ballora, yet Williams wife is not canon yet. This closes it down, reopening to what is Fnaf 2. Nothing happens much here, but a few years after it opens, in 1987, The night guard, Jeremy Fitzergerald is wanted to go to parts and service to check on a withered animatronic, Mangle. He then gets bit in the frontal lobe when checking on her or his head. Then, of course, they reopen, with new animatronics they used last time in the 1970s, except, there is 5 kids in each animatronic that William killed earlier. Nothing happpens here,so it just closes after a little while. Then,in 2023, a closed down pizzeria opens up, where William had stayed for 30 years. He wants to find Micheal because of the 1983 incident,so he somewhat decides to work here. Nothing really happens,but at the end,this building burns down the the ground, with only William and Micheal Surviving. Quick recap, Micheal is now purple guy.The fnaf with five kids dead decides to open up,with not much happening,so it closes down for old age once and for all. The 2nd guy we mentioned here, Henry Emily, decides to make a pizzeria to lure all the souls in, including William,and Micheal. William acts all edgy, by the way now. So guess what Henry does. Burns the place down to the ground, with only William surviving!