I mean, people mating with wolves is a little surprising, especially with this genre being recommended to young audiences.
The story is really not that interesting either. The main character is inconsistent. One moment a remorseless mass murderer, the next moment a supposed good guy. There are entertaining moments, but consistency and a sense of story would go a lot farther than this book’s substitute for story. That is, jokes about anatomy and long, meaningless fight scenes full of unneeded gore, where the end result is not in doubt whatsoever. Just move the story forward.