Centia was a vampire who served Friar Grystok and the Three Mad Sisters. A quiet and shy figure, she appeared to be one of Grystok's personal slaves.
After Rose Tyler was kidnapped by Grystok's pet vampire bat, Hugo, and transported her to the coffin ship on which they worked, Centia was ordered to change Rose into a white gown in preparation for displaying her to the Three Mad Sisters. After the Ninth Doctor caught up to Rose, who had been converted to a vampire herself, Centia asked to help him in return for Rose being kind to her.
Eventually, the Doctor and Centia carried the unconscious Rose to Rassilon's ship and escaped, settling on a quiet moon as they waited for Rose to recover. When she did, she noted how different Centia looked now she was free. As they parted ways, the Doctor recommended she take Rassilon's ship and see some of the universe before returning to the vampires. (COMIC: Monstrous Beauty)