"It is not your skin that sustains me, but your fear!"

Springtrap is the man behind the massacre, "William Afton." He was certainly destined to die from a springlock failure.

His evil deeds caused him to be cast out even from Heaven, and he was hated even by his own Demon, resulting in his soul being cursed to wander the living world forever.

"I always come back."

He overcame death and returned through that curse of hatred, rage, and sorrow. The suit, which has now become his very self, is the evidence of the atrocities he committed.