Mukii was a male Hephaestan politician from the planet Hephaestus. He was president of the Hephaestan High Council in the year 2274.
When James T. Kirk initially met with the high council in 2274, Mukii felt confident that a mining agreement for pergium and dilithium could be reached with the Federation, and arranged for the crew of the USS Enterprise to partake freely of the resort planet’s amenities. When a Hephaestan was found murdered, Mukii did not immediately file charges, although peace officers had arrested Lieutenant Pavel Chekov and a Klingon soldier from the IKS Kluggoth. After events showed that Klingons had been responsible, and Klingons had killed doctors Simaya and Sikaar, Mukii revealed that the two doctors were the only Hephaestans who knew where symbionts were manufactured. (TOS comic: "All the Infinite Ways")