the hookah smoking caterpillar. he quit drugs and now goes around to elementary schools warning of the dangers of that sweet, sweet opium!
Or could you venture into the world of Disney? The original stories of Cinderella and the like are kinda dark.
Rumplestiltskin's daycare services.
Hoggle from Labyrinth. Yeah, overall he is good, but he has a lot of regrets I think. Is there even a book of the movie though?