Zafila is dark skinned, only male, member of Wolkenritter, Guardians of the Book of Darkness. He is, like Arf, able to transform into a wolf, and he was called Familiar many times, although he negates it, saying that he is "Guardian Wolf" of his master.
When not battling, Zafila is almost always in his wolf form, because his ears and tail stays visible while in human form.
Zafila is original counter part of Arf, Fate's familiar. Later, Arf teaches him how to change to "Puppy form".