Okabu tells the story of two Cloud Whales named Kumulo and Nimbe. As everyone knows, Cloud Whales live in a kingdom in the sky. However, when the malevolent Doza machines begin to pollute the Earth, their exhaust and smog quickly rise up into the sky. The Cloud Whales quickly grow sick. Kumulo and Nimbe are some of the only healthy creatures left in the kingdom, and they are dispatched by their rulers to find the source of this illness and scratch it out. Their search leads them to the surface, where they must battle the Doza in extraordinarily laid back fashion.
Quickly upon retreating to the surface, the Cloud Whales find a tribe of nature-loving creatures called the Yorubo. The Yorubo are also being affected by the pollution, and agree to help Kumulo and Nimbe rid the world of its sickness. The Doza have imprisoned certain key Yorubo, and the Cloud Whales must free these creatures in order to enlist their aid.



