What makes it Christian fiction?

I just read a beautiful book about the ministry of Jesus. It's definitely fiction. It's definitely Biblical. But I'm wondering how many of my friends might disagree about its being Christian fiction. It tell the story of Jesus through the eyes of his cat--a character I'd agree can't be found in the Bible. And this cat offers a view of Jesus that might conflict with some popular images. This Jesus laughs. He welcomes sinners. He chooses love over law. And he speaks to non-believers (and a cat)...