Zurfina the Magnificent is a character in The Voyage of the Minotaur and the other books of Senta and the Steel Dragon.
When we last saw Zurfina in Book 0: Brechalon, she was prisoner 89 in the Kingdom of Brechalon's magical prison of Schwarztogrube. Now we find her living in the city of Brech, although it is pretty clear early on that she is in hiding, at least to a degree. Needing a high power magic wielder, the Dechantagne's hire her to go with them to Birmisia. About this same time, she comes into contact with Senta and takes her in as an apprentice.
Zurfina is really not a major character. She is a very important minor character. She acts as a deus ex machina in several situations. She is however in the front of the action in this book more than any of the others, primarily because she and Senta spend so much time together aboard the HMS Minotaur.
Zurfina is fun to write because she is completely self-absorbed. While Iolanthe thinks of nothing but the good of her family, Zurfina thinks of nothing but herself. Even when Terrence chastises her for allowing Senta to almost get eaten by velociraptors, she simply replies. "Children are going to be eaten." Still, her relationship with Senta grows as the story progresses and we see a few hints of affection.