Electra Woman and Dyna Girl are the alter-egos of Lori and Judy, two reporters who work for Newsmakers magazine.
Electrabase, which contains the computer 'Crimescope'.
The backstory of Lori and Judy was never developed or discussed on the show. Watching the show, one can only assume that the two characters live in the same house.
In "The Sorcerer's Golden Trick: Part 1" there is a reference to their past in which Dyna Girl was an Olympic athlete and Electra Woman might have been her coach. But the references they make to each other throughout the series is always platonic, never familial.
