I love the writing in Book 5....I flew through reading Order of the Phoenix, where Goblet of Fire and the others took me a little longer to read (not that I'm complaining!)
But based on the adaptability to the movie, I have loved Books 1&2 since they both had Oliver Wood in them (I can't remember if Book 3 and on do or not ) and Sean Biggerstaff is yummy
) and Sean Biggerstaff is yummy 
Hybrid Mode
