Where is Marty?

One day Mary was walking through the kitchen and saw a mouse. She let out a blood-curdling shriek, which of course scared the mouse away. She began to think to herself, “Where is Marty? I thought cats were supposed to catch mice or scare them off or something.” As she slowly got down from her place of safety, where she had climbed to get away from this horrid creature, she looked over and there he was, right at the end of the couch, curled up asleep. Just when she needed him the most, he was lying down on the job.