Diogo Harari is an young Belter from Ceres
Diogo and several other youths tapped into Ceres water supply stealing the liquid in order to sell in the blackmarket. However, since they were stealing so much water it quickly became noticable to authorities. During a police raid Diogo was captured by Miller who stated that Diogo should be imprisoned for 2 years before releasing him.
Diogo later was on his uncle's mining ship collecting Ice when they were boarded and searched by Martian Navy soldiers who discovered the ships licence to be out of date and shut them down. Later whilst Diogo was sleeping his drunken uncle woke him, threw him in a airlock in his suit into the vaccum of space then procceeded to ram his ice haul directly at the Martian vessel that had previously boarded them, but not before his ship was destroyed by a missile.
Later when Fred Johnson rallys the OPA factions into attacking a spacestation, Diogo joins the assault team. Upon boarding he is hit by an enemy gell round shot, but it unhurt. Diogo hearing that Miller killed the leader of the station crew gains a newfound respect for the former police officer and offers him a place to stay in Diogo's own quarters on Tycho Station.