Keron (ケロン星 Keronsei, Planet Keron) is a planet from the anime and manga series Keroro Gunso. Keron is the fifty-eighth planet of the Gamma Planetary System.
Keron has what looks like green oceans with yellow star-shaped continents with an atmosphere similar to Pekopon's, but overall more humid.
Keronians (ケロン人 Keronjin) are the natural inhabitants of the planet Keron. They are frog-like creatures that grow tails in young ones and breathe in air. It also seems that they can either breathe underwater or they can hold their breathes for an extremely long time. They are sensitive to changes in atmospheric humidity. However in Keroro Land, Keronians can be based on other organisms or objects.
Keronian females are a bit different to males, but can look like a male. Female keronians have "horns" on their hats sometimes, and are more commonly known for keeping their tadpole markings and tail, but some females have been shown with no tail and 'adult' markings. Most, if not all keronians are able to grow hair when they have past half their lifespan or so with very few exceptions.
Nyororos are the natural enemies of Keronians. They suck water from Keronians whenever their water levels rise, essentially dehydrating them.
The Viper clan is a major rival of Keronians and are at war with them for many years.
Pretty much everyone on Planet Keron agrees that at least some things should be handwritten, and sent using the postal service, as opposed to using the Space Internet. -Keroro Gunso episode 228