Myst

She was a demon used to kill Maron. She is a pure breed demon and more powerful than Noin. She had a candy box to hold demons. She was defeated by Maron because Noin tell Maron about the candy box which is Myst's source of power. Even if it was broken by Maron, Maron takes pity and gives back the candy box. (Source: http://en.wikipedia.org/wiki/Kaitou_Jeanne)

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