-Pride of Baghdad
-Bone
-Preacher
-The Boys (the superheroes in this world are corrupt assholes)
-Sin City
-Binky the Space Cat (ok, it's a kids one, but it's fun for anyone who's a cat fan, besides all the other ones I've mentioned so far except for Bone are super dark)
-Amulet (another one that younger readers can enjoy, but I'm an adult and I teared up a little. It's good stuff..don't judge me!)
-Pinocchio, Vampire Slayer
-Wormwood
-Ranklechick the Three Legged Cat
Edit: Oh good, you're cool with manga. In that case
-Petshop of Horrors
-Yotsuba
-Hellsing
-Buddha
-Full Metal Alchemist
-Fruits Basket