Two examples of cartoony yet dark would be:
Conker's Bad Fur Day, and it's remake Conker Live & Reloaded. Although you can label them as mature and offensive, those are just two things that stem from "dark".
Also, I know it looks like a painting. In fact, I consider paintings to be right in-between a realistic and cartoony style. Hence, why I think this is a mix of TP and WW's style. That is what I think, and am not arguing about it with anyone anymore.