I disagree--Nabokov does "get inside" Humbert's head and justify his pedophilia to a large degree--he's the "good" pedophile who is set up against an "evil" one, whom he ends up killing in the end, which is what gets him in jail--not his penchant for young girls.

But back to Dexter--you should watch it 'cause it's entertaining. And on right now, incidentally, although I don't have Showtime.