Bella Huntingdon
Bella Huntingdon was a member of an extinct tiger-like species. In her human form she looked like a pale, 17 year old girl, though she could turn into ferocious tiger when she needed.
Bella Huntingdon came to Earth in the 18th century with her grandmother, Lady Huntingdon. Lady Huntingdon obtained an estate and held a ball every year, seemingly to find a husband for Bella. In fact, she was trying to find a way to get back to her home planet. When she wasn't needed, Bella was kept in a bare room and fed raw meat.
In 1764, Iris Wildthyme and Turner came to the ball, with Iris planning to get Turner to marry Bella and then get the estate in the inheritance. Though Bella was interested, she knew that Lady Huntingdon wanted Iris Wildthyme's TARDIS in return and denied Turner's proposal. When Lady Huntingdon was confronted by the Fourth Doctor, Bella refused to help her. After she was defeated, Bella stayed behind on Earth and married Turner, who had been abandoned by Iris. (ST: Old Flames)