Majo Monroe was Momoko's witch tutor.

She lived in New York, and she worked in a bakery. She was very kind and friendly, she was even offered to be in the senate, but she refused the offer.

She met Momoko in a park. Momoko was all alone and Monroe approached her and gave her a cookie. After that, Momoko was always visiting her.
Many years later Momoko found out that she was a witch, and she became her apprentice. Momoko passed all her exams, and on the day that she got her crystal... Monroe fell very ill and she passed away.

Monroe appeared, a few times, in Momoko's dreams, to give her advice.