I know you're just playin' around, but in reality, Harry Potter isn't any more subersive against the truth of God than virtually any other book, movie, tv show or radio song that says there is no God and since He doesn't exist, anything goes...
See if you can get a copy of "The Hidden Key to Harry Potter" by John Granger ISBN 0-9723221-0-8.
The author makes a compelling case that it is a work of Christian fiction, in the "Inkling" tradition of C. S. Lewis and J. R. R. Tolkien.
I find the entire Harry Potter series full of superb moral lessons, of making the hard decisions, suffering the consequences, and reaping the rewards.
I would be hard pressed to find a better vehicle for teaching about the battle between Good and seductive Evil.