Lady Liana had beef with her doctor because he had overcharged her but he did not do anything that she wanted. She did not get healed from what was affecting her and she was pissed off about it. She had to torture him and she did it with her scat femdom fetish. As he ate her shit, he regretted not doing more for him and he promised never to do it again.
Mistress Mia was pissed at how casual and careless her slave was and she felt that he deserved to be humiliated for him to take his job seriously. So the mistress used her scat fetish to torture him and by the time she was done shitting on him, he confessed that he had dropped the ball a bit and would change and work harder than he had been doing before.