What is the name of the fictional universe that XXX is from?
Little Cheese
In Teen Titans #30-31 (December 2005-January 2006), Little Cheese is mentioned in a series of pages purporting to be a Zoo Crew comic published in the mainstream DC Universe, and follows the adventures of the Zoo Crew teammates in a grimmer, darker version of Earth-C, parodying the recent trend toward ``grim and gritty'' superhero comics.
DC Universe