Hmm .... what about this novel?

I hesitated between 2 and 3 stars to describe this novel .... that mean? I first thought I would not succeed to go to the end of the story, then I "am taking the game," but I do not know whether I liked it or not, the subject is disturbing, the style is disjointed, a little diary reads a dangerous psychopath who takes a little getting a vigilante, we know that some characters will end badly ... And they end badly but it just seems normal and logical, short this is a very special novel, which leaves a strange feeling ....