He is just one of the most superb characters ever created. He's complex, interesting and contradictory; he's bad, he's good, he's mean, he's nice, he's emotional, he's detached, he loves, he hates. He gets some of the best lines, he 'clicks' with every other character, he challenges the boundaries of stereotypical baddies
...................................................................................................................................and yes, i did happen to notice that he was 'quite' attractive.