Cassandra Doe is a mysterious Mahora student recently transferred to class 3-A under a scholarship. Her real name is unknown. She was dubbed "Cassandra" by fellow martial artists in the underground fighting circles due to her ability to read and predict their moves perfectly.
After an unknown amount of Time, Cassandra eventally arrived at Mahora all girls Junior Highschool, using a scholarship to attend.
She assisted during the assault on Mahora by the Wolkenritter, where she defended a weakened Evangeline, a downed Yue, and an incapacitated Nodoka from having their Linker cores drained by Vita.
Since then she has begun regular sparring sessions with Negi in the morning.
Word of God states (acccording to one the posts Negima all purpose Fanfiction Forum) the she will assume the mantle of 'Spoiler' and join the United Magical Girl Association.