Fog was a Ferengi pirate. He claimed to be a DaiMon, but it was unclear whether he actually ever held the rank. Fog was considered aggressive. He left the traditional life of profit and eventually became a pirate, serving under other pirates. He would kill his pirate captains in order to move up in the chain.
Fog served under other pirates, but would kill them, and after twelve years, became his own captain. His band of pirates is called "The Red Band," and operates off the starship Starving Gree. (Last Unicorn RPG module: Raiders, Renegades & Rogues)