Robot-Master is a character in Marvel's Transformers comics.
Interestingly enough, Robot-Master was originally a character in a comic within the Transformers comics, also called Robot-Master. This comic was published by an unnamed comics studio (although there were strong hints that it was Marvel Comics) and written by Donny Finkleberg.
Because of the poor quality and low popularity of Robot-Master, the comic was discontinued and Finkleberg was fired. However, he was contacted by Walter Barnett, who had been ordered by the Intelligence and Information Institute to make up an explanation for the appearance of the Transformers, to avoid panic among the people of the USA.
Barnett and Finkleberg struck a deal, and thus Robot Master was resurrected - although this time as a "real" character. Finkleberg acted as the Robot-Master character, giving long, threatening speeches of him being in command of these enormous robots, and thanks to Barnett's influence, these speeches were broadcast on every television channel in the USA. This was, of course, a sham - but the general public was none the wiser.
Robot-Master's career - and Finkleberg's life - was almost cut tragically short when Megatron and the Decepticons found out about him and tried to put an end to this mockery, to save their honour. However, Finkleberg convinced Megatron that he might be of more use to them alive, because that way he could continue making his speeches, only this time praising the Decepticons and denouncing the Autobots as enemies who want to kill the humans.
However, Finkleberg began to fear for his life in the company of the Decepticons, and escaped them during a battle between the Autobots and the Decepticons. He abandoned the Robot Master character, but was later forced to become involved in a battle between the Autobot Skids and the Decepticon Ravage, along with a woman known as Charlene. During the battle, Skids was rendered inoperative, and Finkleberg covertly sold him to the Rapid Anti-Robot Assault Team for 50 thousand dollars.
Skids, along with a number of other deactivated Autobots, were later used by Circuit Breaker in a fight against the Decepticon Battlechargers. Finkleberg used his 50 thousand dollar reward cheque from RAAT to contribute towards fixing the damage caused by the fight. He was not seen or mentioned after this.
Note: Recently, Takara launched a toyline called Robot Masters, which reused old Transformer molds from various series.