Madame Marissa got late to where she was going because of her loser driver. She had to punish him to make sure that a similar thing never happened in future. So she made him lick the soles of her shoes. They were dirty and she even added her saliva and forced him to lick them clean. He did and swallowed as she wanted. It was not only degrading, but humiliating as well. Just like she wanted it.