Tapu Koko's inner body is solid black in color with white markings on the chest and face. Yellow rings are present on its shoulders and yellow markings appear on the eyes as well. Its lower body is orange and consists entirely of five feather-like appendages. Tapu Koko's hair, similarly is orange with a yellow tip in the shape of a mohawk. Its arms are solid with a two fingered hand on each in the shape of a bird's beak, which are connected to Tapu Koko's shell. The shell is a yellow, egg-shaped dome with multiple geometric patterns on the shell. On each side of the shell is are wings.
Although they are known as the guardian, it does not mean that they often help people. They have strong curiosity, and like to decisive victory by fighting with other Pokémon. It is said that Tapu Koko stores its electrical energy by covering itself with its shell.
This guardian deity of Melemele is brimming with curiosity. It summons thunderclouds and stores their lightning inside its body.
It confuses its enemies by flying too quickly for the eye to follow. It has a hair-trigger temper but forgets what made it angry an instant later.