My sister recently ended her relationship. While in that relationship she took a loan out in her name on her ex's behalf. When they split he agreed to keep paying for the loan and he could keep his car. He hasn't been paying his payments so now my sister is getting letters from her bank saying if she doesn't pay they will take her car. The loan agreement is in her name only as he had a bad credit rating, but the car is in his name. What can she do? And what rights to the car does she have?