I suppose the best I can come up with is Faith from Buffy: The Vampire Slayer.
Though it would be Faith as she is in the last season, and not as overtly sexual or violent. Cassandra, while not introverted, is generally more subtle. Other than that I think they're fairly similar characters.
Though it would be Faith as she is in the last season, and not as overtly sexual or violent. Cassandra, while not introverted, is generally more subtle. Other than that I think they're fairly similar characters.