Rostow was a pilot. He was known as the "Greatest Pilot in the Galaxy".
He was Dr Linus Leofrix's partner. They went to the Ogron planet so Leofrix could conduct his mental augmentation experiments. Leofrix stated at one point that he should have used Rostow as a subject due to his lack of intelligence. Unfortunately for them, the Ogron they picked, Gnork, became smarter than Leofrix. He took their spacecraft, after which Rostow and Leofrix were presumably killed by the Ogrons. (COMIC: Warlord of the Ogrons)