Predisposition makes sense to me, yes! I feel like some humans really enjoying putting different substances in their body. I'm one of them. (:
I've never done meth/heroin but when I am depressed out of my mind it makes perfect* sense for some reason.
Trippy!!!!

Plus I've always been fascinated with books and documentaries about drugs. They are romantically tragic to me or something..

Oh Yeah!!!!!! And if your parents drink/do drugs, that stuff is IN YOUR DNA!!!!