Mistress Vanny was not willing to let her slave get away with being forgetful. He was supposed to be her reminder and if he forgot, then she would be in trouble. So she punished him to make sure that he did not forget anything else. She had him lick her feet which she made sure were sweaty and smelly. She told him every time he forgot something, she would humiliate him. He did his best never to forget things.