Earth is the home-world of the human race. Unbeknownst to most humans, fairies and other magical creatures live among them and are actively helping miserable children or causing mischief.
Fairies have been active on Earth, at least, since the godkid of Cosmo and Wanda invented the wheel. Wanda did cause the extinction of the dinosaurs on "her bad day" (source episode The Really Bad Day!). Cosmo is responsible for sinking the city of Atlantis. Fairies are immortal and do not age. When their godchild has grown into an adult, most fairies return to Fairy World until they are re-assigned to another godchild.
Earth is the home planet for humanity including the following characters: