Jonu was a female Klingon who worked as a bounty hunter in the 2370s. She was one of several bounty hunters hired by Iliana Ghemor to find and kill Ghemor's mirror universe counterpart.
In 2377, Jonu encountered Ghemor in orbit of Harkoum, where Ghemor rammed Jonu's flyer, sending them both crashing down to the planet. Jonu later pursued Ghemor on foot. During the chase, Ghemor detonated a weapon in Jonu's path, fatally injuring the bounty hunter. Ghemor refused to kill Jonu and spare her more pain, as he felt a Klingon who fought their battle for money had no honor. Jonu believed she would travel to Gre'thor after her death. Before she died, she prayed to her ancestors to drown the Cardassian woman in a river of blood.
Ghemor took Jonu's D'k tahg with her, although she dropped it when she encountered Savonigar. The Nausicaan recognised it as being Jonu's. (DS9 novel: Warpath)