Glitchtrap

He is a digital entity, heavily implied to be a digital manifestation of William Afton's consciousness, possibly trapped within a circuit board containing old Fazbear Entertainment data. This data was scanned into the game, and Glitchtrap emerged, attempting to influence and control players, particularly Vanessa, who becomes his minion, Vanny. In Pizzeria Simulator and Ultimate Custom Night, William Afton seemingly meets his end, but his digital consciousness survives, possibly trapped within old Fazbear Entertainment circuit boards. When Fazbear Entertainment scans these circuit boards for Help Wanted, Glitchtrap is brought into the game. Glitchtrap, as a digital entity, attempts to corrupt and control players, most notably Vanessa, turning her into Vanny. Vanny is presented as a follower of Glitchtrap, possibly acting as his physical agent or vessel in the real world. There's a theory that Glitchtrap might be the Mimic, a character in the Ruin DLC, further complicating the lore.