Lady Johanna does not like to beg. She needed money and since she could not beg for it, she had to force it out of this guy as she knew he had the money. She tried asking for it but he did not give it to her so she turned him into her human toilet and he had to pay her in order for her to stop shitting on him.
Lady Johanna knew what she was doing when she tracked down this guy and she degraded him before she engaged his services. She knew how good he was and she knew she needed his services. But she could not afford them. So she took a shit on him and she forced him to swallow it and made herself appear to be dangerous so that he could not even dream of asking her for money. He did what she wanted for free.