The Purple Man first appears in a death mini-game in FNAF 2. The mini-game shows Freddy taking care of children at a birthday party. There is a sad child looking in, and the player watches as The Purple man drives by, gets out and murders the child and then drives away.
We see him again in another mini-game, this time when playing as Foxy. Foxy runs out twice to see the children. The third time, we see The Purple Man, smiling. When Foxy enters the room, there are five dead children in the room.
Some theories state that The Purple Man is the Phone Guy. Phone Guy always speaks like an outsider looking in, he refers to the management as “they” so he’s not a higher up like the CEO or even a manager. He’s also not a day worker because he says things like “the employees” and “the staff”. So he works there but isn’t considered a regular member of the company. He’s qualified to take over as night guard, as we learn he plans to take over the position sometime after night six in FNAF 2. He has been with the company a long time, since he worked in the first pizzeria. His favourite animatronic is Foxy and we see The Purple Guy smiling as he watches Foxy in the mini-game. Purple Guy and The Puppet wouldn’t get along, seeing as The Puppet was the sad child The Purple Guy killed in Fredbear’s Diner. The Phone Guy says he doesn’t like The Puppet because it’s “always thinking”. We know the killer is a security guard because during the Save Them mini-game, while Freddy chases The Puppet and The Purple Man appears and chases Freddy. On his chest, is an orange badge, the kind that would be given to a security guard. His eyes also resemble Golden Freddy’s. In the Purple Guy’s hand is a phone.
In FNAF 3, we see Purple Guy hiding in a secret safe-room that has been built into every pizzeria, a room that’s hidden to customers and invisible to the animatronics’ programming.