Candy is first seen when Batman infiltrates the ship, the Final Offer. She is present when Cobblepot is torturing Alberto Falcone and even gives Cobblepot a summary of the torture so far. When Batman enters the room, she screams and runs behind a desk.
When Deathstroke and Batman fight in the boiler deck, she, Tracey, and Cobblepot can be seen watching the fight. After Batman defeats him, the three retreat into Cobblepot's office for the rest of the game.
It is assumed that she later quit Penguin's gang or was killed for some reason, as she is never seen or heard from in the later Arkham games.
Candy was raised on the streets, but managed to pull herself up and earn a business degree. Unfortunately, lean times and a contracting job market caused her to fall in with Penguin's Crowd. The recession has driven many well educated people to take desperate action to support themselves, but that's no excuse for criminal behavior. Her crimes are minor, however, making her an excellent candidate for rehabilitation