Rahmin was a Caatati who captained a ship of refugees. When encountered by the USS Voyager, he explained that his people were assimilated by the Borg and were left with nothing. Captain Kathryn Janeway offered him supplies, but when he saw Seven of Nine, he became outraged. Rahmin demanded that Janeway not only give him more supplies, but Seven as well. She refused, and Rahmin threatened to destroy Voyager. A solution was found when Seven offered to build the Caatati an energy matrix so that the Caatati could have all the power they needed. (VOY: "Day of Honor")

Rahmin was played by actor Michael A. Krawic. The novelization of the "Day of Honor" television episode gives the character's full name as Temmis Rahmin.