This sounds like a perfect middle-grade story. It has everything from grieving the loss of a parent to trying to save the city from the chief of bad guys. I love seeing this young boy team up with a monster to help get revenge for his father. I think that will grow into a great friendship that will help him move on. I have never really been one to read a lot of middle-grade stories, but I think this one will be great for a lot of kids.