There have been many attempts by good Christian writers to "sneak in" Christian concepts into their stories in order to reach out to a greater audience. Tolkien and C.S. Lewis readily come to mind. A few weeks ago, I noticed a news article that claimed that Rowling had also done that in her Harry Potter books.
The site that Irish Hermit pointed to says "Since this book series is full of references to "Glaux" (the name of their god), some readers may even equate these "noble" tales with Christian parables. Without faith in God's Word and knowledge of His warnings, few are prepared to discern the deceptions. Enticed by the dark, scary thrills, many will gladly accept the lies."
I have not read this particular book and do not know if the author is sneaking in Christian concepts or is making his own concepts similar to Christian ones. OTH, it is true that one could be tempted by the dark side in any of these books and movies where the good and evil battle. I suspect that we can do bad and descend into evil even without such books and movies. However, as the preface to The Exorcist warns us, it is certainly dangerous to delve into the occult (as something more than fiction) as this opens up the door to the devil and his demons.