The mutant superhero known as Rogue started out as a villain. This was due to her troubled past that led her to being raised by Mystique.
After permanently absorbing Ms. Marvel’s memories and power due to her mutant power not functioning properly, she reforms and joins the X-men.
Although her backstory is well known, Rogue’s personal information was shrouded in mystery until the Rogue Comic Series released in Sept 2004. In this series her name revealed as Ann Marie.
Rogue first appeared in Avengers Annual #10 (1981).