Kitai

Kitai was a Pakha, a hamster-like humanoid who attended the wedding of Bernice Summerfield and Jason Kane, later being hypnotized into posing as The Master so he could make his escape (NA: Happy Endings)

Biography
Kitai was one of the wedding guests present on Benny's special day and was caught up in The Master's shenanigans, being hypnotized into posing as the villain to fool the UNIT soldiers and allow him to make his escape.