Once remembered as the man known by William Afton, Springtrap has become a burnt husk of a soul. The serial killer behind the Missing Children Incident of '93, it is ultimately his actions that bring to life the possessed animatronics at Freddy Fazbear's Pizza. This karma eventually catches up to William, as the restless souls return to have their vengeance, trapping them in an abandoned location. After being rescued decades later for an American robotics expo curated by President Biden, he forgets one thing (memory loss aside) as he holds the grand opening. He always comes back.

Here's an example of what William Afton sounds like as Springtrap: https://www.youtube.com/watch?v=xZldtw9NoFg