Yeah, the crappy thing with the movie is how much it had to drop in terms of character development. It's a great film, but Kiriyama goes from being the tragic sociopath he is in the book to being an unhinged psychopath who volunteers to play the game so he can murder people. An understandable change to condense 600+ pages of book into a single film, but still... :)
RE: Battle Royale and the Tragedy of Kazuo Kiriyama