This mistress loves to torture and out of all the methods she normally uses to do it, peeing on slaves is her best method of torture. When this guy pissed her by lying today, she had to show him what the consequences of his lies were. And she trampled him with her bare feet before she peed into his mouth and had him drink her urine. He was shocked but he was also afraid so he cooperated with her.
This mistress was pissed that she had a lazy slave. She had given him a lot of chances to change but she was afraid they did not help. So she had to step in and make sure he changed. She searched for what to do and how to do it and she settled on using her pee to do it. The mistress fed the guy with her pee and that is how he stopped his laziness.
This mistress was so pissed with this girl that she knew she had to do something the girl had never gone through before. So the mistress chose to use her kinky pee fetish to degrade the girl by asking her to wash her face with her pee and when she was done, she was made to drink the same pee. That is how the girl came to learn her lesson cruelly.