My DS has an obsession with books too. We go to the library every fortnight to pick out three new books and by the end of the two weeks I know them by heart and DS can tell if I try to skip a page or read it wrong His favourite books are the Todd Parr ones because of the bright colours I suppose. He will happily sit all day and have books read to him - drives me nuts! - but as most have said, it's a good obsession to have