Frobisher

Frobisher was a Whifferdill, a shape changer who travelled with the Sixth Doctor and Peri and then the Seventh Doctor for some time. He also encountered the Eighth Doctor.

Frobisher was once married to another Whifferdill named Francine.

Meeting the Doctor
Frobisher first met the Sixth Doctor when he was a private investigator calling himself "Avan Tarklu". He came across the Doctor when an enemy of his, Dogbolter, placed a bounty on the Doctor. After infiltrating the TARDIS, instead of turning the Doctor in for the money, Tarklu decided that he liked the Doctor and helped him against Dogbolter. He then joined the Doctor on his journeys. He assumed the name of Frobisher because he felt that it sounded British and thought that the Doctor would like that. (DWM: The Shape Shifter)

Frobisher ran a bar later, having morphed into the form of a human. He met the Eighth Doctor there but did not recognise him. He talked with the Doctor trying to find out why he looked so sad. When a robot called Zalda entered the bar threatening to blow herself up, the Doctor convinced her otherwise. Frobisher then called for drinks on the house. He then morphed back into his penguin-like form. (DWM: The Flood)

Behind the Scenes
Frobisher has only ever appeared in audio, book and comic adventures. Robert Jezek is the voice of Frobisher who is given an American-Brooklyn style accent, he does this in BFA: The Holy Terror