Information in this article may not be canonical to the storyline of the games or any other Sonic continuity.
The Kiki is a character mentioned in the Sonic the Hedgehog comic series and its spin-offs published by Archie Comics. It is a mass-produced, monkey-based Badnik model created by Dr. Eggman.
When reality was rewritten by the second Genesis Wave, the Kiki became a part of Sonic the Hedgehog's new history where many models of it would be destroyed by him.
Later on, in a fight between Sonic and Buster Rod G, Sonic would mock Buster by calling him "Kiki" and mention how many times he had destroyed them.