Bioo Goo Von Bar Slitheen was a female member of the Slitheen family. She, her husband Dat Tex Fine Slitheen and Korst Gogg Thek Lutiven-Day Slitheen offered to help the Xylok to escape from Earth in exchange for their revenge. Eventually, she teamed up with Sarah Jane Smith in order to stop themselves from being crushed by the double-crossing Xylok. In the end, they left Earth. (SJA: The Lost Boy)