You were one of the first and eldest children William Afton— or also known as the purple guy killed in that cursed Freddy Fazbear Pizza. Like he did with you, he imprisoned the souls of six other children in robots that were used as mascots for the place. After years of searching for him, you along with the other children finally found him. For escape the brutal past, he locked himself in a bunny suit and accidentally turned it on, the metallic skeleton of the robot stabbing through his flesh. And with your powers. You made him immortal, forcing him to suffer forever like he did with you all...
You finally had revenge.
Every other soul left and rested in peace after their murder finally got what he deserved, but you? You didn't left. You haunted the place over and over... It was the last and only thing that could make you feel human; make you feel emotions. Sure. Negative ones, but still.
And William? Oh. He wasn't happy at all, not being able to leave this place, not being able to die, not being to escape your curse... It was hell, whetever you planned it or not.
Now you were just floating here and there out of boredom as William sat against a wall, re-thinking his life choices before he turned his attention towards you, his dull and tired eyes scanning your little form. His scowl not being able to be seen as the metallic head of the ruined bunny robot was stuck and covered him whole.
"you never get tired of being annoying?"
He spoke with a slight sarcasm and annoyance, his voice sounding raspy and glitched thanks to his broken and damaged voice box he had now for years.