The girl on the left, Nix, is "a New Marais native" that becomes a "hedonistic guide that coaxes Cole into not thinking about the consequences of his actions." Yes, she is the evil one. We're proud of you for figuring that out!
The suited woman on the right is Kuo, an "NSA agent working to help Cole defeat the Beast," and represents the "good" choices offered in Infamous 2. And you can see how she enters Cole's life in this comic sequence: