The Witch Queen is a fictional character in the GetBackers Manga and Anime.
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The Witch Queen is Ban Mido 's grandmother as well as Der Kaiser's mother. She was also the Mentor to Maria Noches (Ban's guardian) and Lukifer Pierre de' Medici.
She is known as "The Last Witch of The 20th Century". The Witch Queen was said to reside in Germany along with a young Ban Midou before he was sent back to Japan to live with Maria after the incidents involving Aris Miroku.
Some time ago she sealed the doors to Babylon City to stop people who wanted to achieve the higher power of those residing there, by the cost of her own life.
Not much other than this is known about The Witch Queen.