Major Neff served as an officer within the Imperial forces, specifically assigned to the Black Sword Command. Stationed in the Koornacht Cluster, Neff found himself present during the Yevetha uprising on N'zoth. This revolt, occurring in 4 ABY, was a response to the oppression they faced from the Imperial shipyard [Black Fifteen]'s personnel and spread throughout the Cluster, resulting in Neff's capture.
Despite being captured during the revolt, Neff lived through it and played a key role in creating a clandestine slave circuitry. This circuitry was utilized by the remaining Imperial prisoners to liberate both themselves and their ships from Yevethan dominion twelve years later.
Michael P. Kube-McDowell mentions Neff in his novel, Tyrant's Test, which is part of the The Black Fleet Crisis series.