Madame Lamia was Count Grendel's surgeon and engineer. She constructed the androids that Grendel used in his plots to kill Prince Reynart and the Fourth Doctor. Although she was a commoner, she and Grendel had a romantic relationship of some kind, although she herself acknowledged that he was not as devoted to her as she was to him.
After an android of Romana I failed to kill the Doctor at the Pavilion of the Summer Winds, she ran out of the Pavilion, but was accidentally shot and killed by one of Grendel's men. (TV: The Androids of Tara)