William Afton (also known as Pink Guy and Dave Miller) was the responsible for The Missing Children Incident mentioned in the original games. He is the designer of the Sister Location Animatronics and is the former owner of Circus Baby's Rentals and Entertainment.
William Afton is only ever seen in various minigames in Five Nights at Freddy's 2. He is represented as pinkish-purple colored (hex code: ee82ee) with black eyes and a large grin.
In sister location you play as William's Son: Michael Afton.
His background is mostly told via silent actions within retro-graphics, or by reading between the lines throughout the games. Between his minigame presence and piecing together information gleaned from the phone calls as well as the posters in Five Nights at Freddy's..
William Afton is the murderer of the six children that sparked the downfall of both Fredbear Entertainment and Fazbear Entertainment, and started the chain of events that leads the players through the series.
Judging by his actions and appearance within the Foxy Go,Go, Go! minigame, William Afton is cruel and cold-blooded, taking pleasure in his crimes with an unceasing smile.
In Sister Location, William tells his son, Michael to go into his own factory and rescue his sister. Whether this is out of fear of the animatronics, or something else, is unknown.
Role in Five Nights at Freddy's 2
In Five Nights at Freddy's 2, William can be seen in the Foxy Go! Go! Go! Minigame.
On the third playthrough, William who killed the Crying child in the Take Cake to the Children game is seen standing in the corner of the starting room, smiling. When Foxy approaches the children, they seem lifeless. The minigame ends with Withered Foxy's jumpscare.
Role in Sister Location
In the opening cutscene of Sister Location, an interviewer is heard asking him questions about the new animatronics. They inquire why certain features were added and express their concerns, but he avoids answering the specific features they refer to.
There is some speculation on this, and one theory is that the 'certain features' that the interviewer was questioning about was the fact that all the animatronics were hollow around the midsection, being just wide enough to fit a child inside. This is further proved by more than a few things.
Firstly, William, in the cutscene at the beginning of the game, is avoiding any questions about the other features. He is the creator of the animatronics in Sister Location, and him being a child killer, he probably made the cavity in the animatronic's just for that specific purpose.
Next, in the Cupcake Minigame, if you successfully grab the ice-cream and go back to start, the game will render you unable to move, just as a blonde little girl walks over. As soon as the child touches Circus Baby, the game emits an earsplitting screech, as Baby's demeanor changes to that of the animatronics from Freddy Fazbear's Pizzeria, and opening up her chest cavity, snatching the child an stuffing her in her midsection, killing her.
Another great reason is that when the player clicks on the 'Extras' button, there is a screen with the animatronic's names, showing blueprints of the robots. Looking closely at any of them, you can see the 'stomach' is more of a bubble. Looking at Funtime Freddy, you can see a small body filling this space
This is one of many theories, and what the features really are is still a bit of a mystery.
Role in The Silver Eyes
According to the novel, Afton originally owned Fredbear's Family Diner alongside Charlie's father, Henry. Being the mechanical genius that he was, Henry created the two springlock suits, one in which William would use in his killing sprees. On Halloween, 1982, Afton donned the Spring Bonnie suit, and he kidnapped and murdered Sammy, Charlie's twin brother, when they were both toddlers.
While William was suspected of committing this murder, he wasn't charged; as a result, the diner ends up closing down. Freddy Fazbear's Pizza was established a few miles south of Hurricane, Utah, and once again, Afton disguises himself as Spring Bonnie, lures five children to the backroom, murders them, and hides their bodies.
One of his notable victims was Michael Brooks, who later went on to possess the Golden Freddy costume. This time, Henry is also suspected of committing the murders, but, considering that the bodies were never found, he was let go. Out of grief, Henry commits suicide, and the pizzeria is closed down, and a mall was built over it.
Ten years later, a memorial was held by the parents of the late Michael Brooks, and Charlie and her childhood friends return to Utah to attend it. They meet with a security guard named Dave while they were revisiting the pizzeria for the third time; they begrudgingly take him along, but Charlie notices a series of scars on the back of his neck.
Dave goes into the backroom, and he retrieves the Spring Bonnie suit, thus revealing that he was the killer all along, and he kidnaps Carlton, one of Charlie's friends, putting him in a spring lock suit. When the group of friends notices that Carlton was missing, they report it to the police department, but action wasn't immediately taken, due to Carlton's habit of being a troublemaker.
A police officer does go to the pizzeria to investigate, but he's immediately stabbed to death by Afton. Carlton wakes up to find himself in an old, malfunctioning springlock suit; William warns him about making any sudden movements, and he takes his shirt off, revealing more scars from a springlock incident.
Charlie and her friends return to the pizzeria to search for Carlton. William confirms that the animatronics were being possessed by the ghosts of the children, and that they were going to kill Charlie and her friends out of confusion.
When told that they would also kill him, he expressed no concern, stating that as long as he had the Spring Bonnie suit on, he would be safe from the children's wrath.
As the group was about to leave the pizzeria, Afton grabs Charlie by the back of her neck, and threatens to choke her to death.
Remembering how the spring lock suits operated, Charlie reaches into the neck of the suit and sets off the spring locks, piercing Afton and killing him slowly. The main animatronics--Freddy, Chica, Bonnie, and Foxy—appear, and they drag the dying Afton away. He presumably becomes Springtrap.
- For the longest time Michael Afton was thought to be the same entity as William Afton, but it was figured out in the final cutscene in V. Hard Golden Freddy mode (Custom Night) that he was not.
- William seems to have a British accent, with his Daughter and Son having one too.
- William seems to have (at least) 4 children, his son Michael, a daughter (Pigtails Girl), younger son (FNaF 4 Crying Child), and an older son (Foxy masked bully).
- Although some believe that the Foxy masked bully is in fact Michael, making a total of 3 children.