Sibyl

The Sibyl started a soothsaying cult, the Sibylline Sisterhood, in Pompeii. She lay down the Sibylline Oracles.

It is unknown why the Sibyl started the cult or what she used it for, but the Tenth Doctor stated that she ran the cult less violently than when they tried conquering Earth with the Pyroviles in 79. The Doctor described her as a "hell of a woman" and "could dance the tarantella." The Doctor also mentioned she had, "Nice teeth." It was said the Doctor had a brief relationship with Sibyl, but he thought that it wouldn't work, to which she replied "I know." (TV: The Fires of Pompeii)