|Location|| 3rd planet from the Sun, the Orion-Cygnus Arm, Milky Way Galaxy.
Near Quasar 3C 405.
Earth is the name of the planet on which almost all of Powerpuff Girls Doujinshi takes place, and a small portion of Grim Tales. There wasn't much focus on the whole world until Chapter 9 of Powerpuff Girls Doujinshi. After Bell has placed a Time Bomb in Megaville it exploded and caused the whole planet to get in the explosion. They probably went back or forth in time, but this is all still unknown.
The Earth that PPGD takes place on seems to be where all characters of major Cartoon Network, Nickelodeon, and Warner brothers cartoons reside. Mostly ones of the 80's and 90's or are of great popularity. It has also been implied that heroes of the DC Comics universe reside there as well. For consistency and fun, the inhabitants aren't drawn in the usual way they were in they're respective shows, but rather a manga/anime look. On the Earth are besides humans and animals (and animals of a antropormorphic cartoon nature), which are the only life-forms on Earth plus plants, also a variety of other species. It is known that there are many humanoid robots and other varaties of those around, for example Jenny, Dib and Bell. There are also ghosts, like Danny Phantom, and meta beings, like the Powerpuff Girls.