FRS IS Target. It's Financial and Retail Services, one of the Pyramids of HQ (like Stores, Facilities, Legal, Merchandising). They issue all redcards (which are underwritten by Target National Bank, which can be simplified to Target Corporation.)
You bet your ass they can fire you for being delinquent on your card, though I'm surprised they don't have a provision for garnishing your wages to start repaying the card (that's probably governed by federal labor laws, superseding Target.)