Explanation:
Bonnie Glade is a person born from magic and metal, when her father (Fritz Glade) and her mother (Eleanor Glade) failed to conceive a daughter her father, out of frustration, made the mimic and purpose built it to grow and extend over time.
He also had it observe the behavior of its soon to be classmates.
Taking a vial of his wife's blood and the mimic to Elizabeth’s house, with the help of her magic and the blood the robot grew lipids, fatty tissue, cartilage, veins, arteries, and faux organs, and hair.
Bonnie was born. Over time as she attended school she grew close to a boy, Gregory, and in turn he grew close to her.
However as time passed more and more things would go wrong with her, the code inside of her brain was left to write itself and eventually it broke, turning into nothing but a jumbled mess of java and html script.
The solution she came to was that she would need a soul if she wanted to be complete.
Somewhere in her mind she thought the ultimate act of love was to capture the soul of the person you care the most about.
The Mega Pizzaplex was the perfect trap; she corrupted the M.X.E.S, the animatronics, the S.T.A.F.F bots, and even created her own two personal followers based off of Princess Peaches pet rabbit, Mips. All to hunt Gregory and bring him to her so she could obtain his soul.