I have a friend who's not very interested in playing RPGs, but he's a Harry Potter nut. Is there a decent (probably fan-made, I've heard that an official HPRPG is unlikely) system that is easy for a new GM and is either specifically for the Harry Potter universe, or from a general RPG system that can be played as-is in a Harry Potter setting?

**Note:** When I say 'easy for a new GM', the game would ideally have between 20 and 100 pages. Shorter is better, but if something is too rules-lite it becomes unplayable, especially for someone with no GM experience. I also want the system to capture at least part of the feel of the magic in the books.