I started watching an anime called GANTZ yesterday and well, I managed to finish it today and I would say that it was way better than I expected. It's a really troubling anime that made me reflect about life and death but also about the society we live in. It also made me feel a sensation that I haven't had since a long time while watching an anime and I would even say that it "marked" me in some ways. The development of every characters and their own stories was awesome and all of them were bound together in the end what I found totaly astonishing. In summary, GANTZ is a damn good anime that everyone should watch at least one time in their life (With the gore and sexual content left apart... even if in my opinion, it was a nice complement to the anime.), because believe me, it really worths the watching!
and after you have watched anime you should start reading manga! It's more mindf*cking and gore than anime (and it's still continuing).
Well I'll probably read it then. Thanks for the advice! :)