Chantho
Chantho was a female Malmooth, and the last of her kind. She left her dead city and worked with Professor Yana of the Utopia Project. When Yana discovered that he was in fact the Master in Human form, he fatally wounded Chantho with a live electric cable. (DW: Utopia)
Her final action was to shoot the Master, triggering his regeneration.
To be polite, Chantho, like all Malmooth, had to say the start of her name at the beginning of each sentence, then finish with its end. For example, when Martha asked what would happen if she didn't speak that way, her reply was, "Chan-That would be rude-tho." However, she was able to overcome this with a certain degree of effort, as she demonstrated to Martha to Martha's amusement. (DW: Utopia - deleted scene)
With Chantho's death, the Malmooth became extinct. Following her death the Futurekind Chieftain along with his minions fed on her remains, when The Master, Martha Jones, Jack Harkness and The Doctor escaped into the year 2007.
She is shown in The Doctors flashes of people who have died in Journeys End.
