I'm praying for you. That thread Animedude suggested? My very own. I too have been struggling with the temptations of porn, lust, hentai....you name it, I've struggled over it. You're not alone in this grueling fight
There's two things up there that you've mentioned you don't do that I would suggest doing. Prayer and reading your Bible. Trust me on this, it works wonders. When you feel the temptation pulling you, pray about it "Lord, please keep me clear and away from this..." and then flip open a Bible (I usually go to the Psalms) and read a couple of verses. Then I usually will shut down my computer to avoid further trouble, and go do something else for a bit. It takes time and patience to get rid of these risky habits. I know from experience, I truly do.
I hope my words have had some effect on you. You're not alone!!!