Bonnie Parker's backstory is closely tied to her historical counterpart, the infamous criminal Bonnie Parker, who was known for her association with Clyde Barrow. In Majo Taisen, she is portrayed as a powerful witch and an outlaw who participates in the deadly Walpurgis tournament, where witches fight each other to fulfill their ultimate desires. While the specifics of her history as a witch are not fully revealed, her demeanor and abilities reflect her past as a notorious figure. She is skilled with firearms and uses her magical powers to enhance her outlaw status, creating a fearsome presence in battle.