Origin
Contessa Erica Alexandra del Portenza is an enigmatic figure whose background is unclear, so much so that her noble title and European ancestry has never been confirmed. She apparently possesses a lengthened life span and may have been born thousands of years previously. She has been head of the criminal genetics group the Agenda.
Creation
Her first appearance was in Superman: The Man of Tomorrow #1 in 1995.
Character Evolution
While being portrayed as an enigmatic figure, it has always been as a sort of parallel to that of Lex Luthor, her former husband. They share a single child together, Lena Luthor. She has been shown to have associates among many powerful people, including Klarion the Witch Boy.
Major Story Arcs
During a period when Lex Luthor was forced to abdicate his control of LexCorp, the Contessa purchased a controlling interest in the corporation and ran it herself. Luthor was forced to regain control of LexCorp by marrying her. She soon after gave birth to Lena, but not wanting any interference, Luthor had her continuously drugged and hidden from sight, though she eventually escaped, taking Lena with her. Although the child was later returned Luthor bore a grudge and just before he became president of the United States he arranged a missile strike on her stronghold, though a body was never found.
Powers and Abilities
She is a cunning businessman and a skilled tactician. She is also immortal, though, presumably, she was killed in the missile attack that Lex Luthor launched against her.