This site is for anybody who's drawn to sophisticated villains, strong-willed supporters, and tortured heroes. If you'd rather cheer for the guy (or lady) who makes ascerbic comments than the happy-go-lucky preppie-girl (or boy...), well you've found true paradise, I think. Basically, each of these characters has some kind of twisted personality trait, unusual history, or generally weird attitude that sets them apart from the norm. It helps if they've killed a few people, but that kind of varies with the situation. It doesn't take much of a dark soul to stand out among the Care Bears, for a particularly loathsome example, but you've got to be pretty messed up to bring down the End-of-the-World-types of X/1999 or Utena.
Before anyone brands me as original (hardly likely, but possible) allow me to point out that fascination for not-so-good guys is neither new nor limited to the brand of American culture that blankets the globe. Folklorists offer the generic term "Trickster" for this sort of character, and they're as old as the hills and just as hard to avoid. (If you're curious, here's a little rant on the antiheroes of old.) Every culture's got one (or more), and even though the names may change (Spider, Loki, Puck, Fox, Brer Rabbit) the song remains the same. So tuck in, and enjoy. You might find some familiar faces along the way, but don't get fooled into straying from the path...