From ROI Wiki

Julius (no last name is specified in the book) is a highly trained and capable agent of Earthfleet's very own Fleet Intelligence corps. He, along with his partner Mary, are highly trained field agents who are assigned to work with Phyland as office staff "officially", and as his body guards unofficially. It is this dual role that has saved Phyland's life several times, and even that of Chancellor Nordham, although the latter occurred more by fluke than intention.