Cassandra is mentioned in the current update in one scene. She will make her appearance in person in the next update.
Cassandra is one of the most promising students this year, and also Sarah's old team-mate. She specializes in Debilitating magic, and upon learning how in-demand her specialty is did not hesitate to dump Sarah in order to become more popular. She is seldom seen without an entourage of fans, and considers herself to be the most powerful student in the school.
Whether that is true, or a part of her over-inflated ego is up for debate.
Since she appears as an antagonist, I decided to go with some more humbling personality changes for if you decide to enslave her. One of her unique personalities is a maid, and the other a cow-girl with some horns and an extra pair of breasts as a couple physical changes to go with it.
I wasn't entirely sure what direction to go with her cow-features, since there are several styles (cow-pattern skin vs normal, horns vs no horns, single set of large breasts vs two sets) So, I picked more or less at random. If you happen to have any particularly strong feelings about the style, be sure to leave a comment or send me a message. If people greatly prefer certain features I can make adjustments before finishing the update.