Dax Fex Fize Slitheen

Dat Tex Fine Slitheen was a male member of the Slitheen family, married to Bioo Goo Von Bar. He posed as Jay Stafford and attempted to avenge his family after their defeat by Sarah Jane Smith. He ended up forming an alliance with her, after he had been double-crossed by a Xylok. He eventually left. (SJA: The Lost Boy)