Lady Yuna had never punished her slave for as long as he had worked for her. The slave never knew there was anything called punishment and he was not prepared for it when it finally came. She used her shit to dominate him and he had to eat her shit and drink her pee. It was brutal and it was degrading but he did not have a choice but to eat and drink.
This guy made fun of lady Yuna and he thought it would end with some laughs but he was shocked when it ended with him eating her shit. She did not react to what he said. She waited for the opportune time and she cornered him then she made him eat her shit. The mistress did not care what he felt or whether he was joking when he made fun of her. She never wanted him to do it again and she ensured that by shitting into his mouth.
Lady Yuna despised this loser and she wanted to show him just how much she despised him. She did not want him to think that she liked him in any way or that she could stand him. So she lured him to her house where she turned him into her human toilet. He had to eat her shit and drink her pee before she let him go having understood how she felt about him.