Kuki and Miwa are high ranking officers of the Mu, they operate under the command of Maya Kamina. They are the ones that deploy the Dolems and later in the series take direct control of Dolems themselves. Not much is known about Miwa, but Kuki has a history with Kunugi. He went undercover as an Earth Federation officer and was the one that ordered Kunugi to carry out the first attack againts the Mu. His agenda was to start the Mu war and give the Mu an excuse to attack back and make them seem as if they were taking the defensive stance. In essence, he was there to engineer a fake war. After the disastrous effects of the Mu attack with their Ritardando Dolem, Kuki mysteriously disappears, though in reality he just went back to Mu territory.
Along with Maya, Kuki and Miwa were branded as traitors to humanity. Towards the end of the series, Kuki is killed by Kunugi in a suicidal attack and Miwa is also killed piloting a dolem.