They are seen acting as security guards for inter-dimensional customs. The Gromflomites make their first appearance in season one, episode one, called 'Pilot'.

Rick accomplished this seemingly difficult task by changing their intergalactic currency from a one to a zero. They would continue their control in the universe and the Galactic Federation until Rick Sanchez eventually dismantled it after escaping on their maximum security prison. Any other information on their historical background is unknown. The majority of Gromflomites depicted on the show happen to be soldiers, but they are otherwise not implied to be a wholly militaristic society, with civilian Gromflomites making some appearances. At least one Gromflomite, Krombopulos Michael (an assassin), has taken on jobs that sometimes require action against the Federation, including the killing of Federation-aligned Gromflomite guards, suggesting that the species as a whole may not be loyal to the Federation.

At some point in time, the Gromflomites took control of the Galactic Federation. Gromflomites are shown to comprise the entire upper echelon of the Galactic Federal government, as well as most of their military, the latter referred to as the Galactic Militia.

Rick and morty bureaucrats