Between the novel and the manga, I decided to read the manga. But maybe I should have started with the movie. The plot is catchy, and all is so crazy and gore. At first I almost quit, because of the artwork. It looked funny, almost cartoonish. And I don't like when the mangaka overdoes the crying: lots of tears, runny noses, dripping saliva over the chin... But it is a good story and very graphic. I can't wait to watch the movie.
Being said that, I will not continue with the manga. My main problem is that I can't stand that there is a woman being raped. And that sadistic, disgusting Instructor... I can handle violence, death, but not women being raped.