Too Risque?

Okay, readers, I'm trying to come up with a cover for the sixth Thaumatology book, Hammer of Witches. This is what I've got, but the question is, too risque? Your opinions sought.

PS. This isn't the final version if I do continue with it. It needs some additional work, but I wanted to see how the fire effect would look and work out whether it was a good plan to go with.