Aucturrim is a large island (considered a continent by most) with strange towers broadcasting strange energy. When the animals are able to pick up its signal, they absorb it and transform into Kairi. Humans have invented ways to harness this energy and to exploit the Kairi for combat, companionship, protection, or profit.​

There are six elements: Fire, Toxin, Aether, Stone, Plant, and Storm. There are also six classes: Domestic, Hunter, Brute, Doctor, Critter, and Armored. Kairi can change element at will (which affects their appearance), though their class, which determines how they fight, will always stay the same.

Aucturrim's nations battle for control of the towers and the Kairi that put their cities in danger. Many people make money off of raising Kairi for businesses, storing them for collectors, and protecting others from them, but many also raise Kairi for war with other nations. The world is dangerous, so many have begun raising their own team of Kairi for battle and protection, known as Kairi Trainers.

The beings who guard the Six Broadcast Towers, who are said to have created them according to myth, are challenged by Kairi Trainers as a test of skill and to quell the tower's harsh signals. As a safety precaution, Trainers must seek out permission to battle these Tower Guardians, given out by receiving endorsements from the nation's many ambassadors. Those able to defeat the Tower Guardians are rewarded with ribbons, but few seem to have the dedication to obtain all six ribbons.