When this guy tried to bully mistress Lina, he did not know that he had messed up with mistress Katya as well. The two of them are super close and they not only do things together but when you have messed with one, you have messed with the other. And that is what happened here as they ganged up on him and they trampled him with their shoes while he was naked.
This mistress did not like how lazy her slave was. So she called her friend and she let her have a go at the loser. The two mistresses had a great time torturing the guy who they had stripped naked. He cried as they trampled and did crazy things to him including whipping him. He could not believe what they were doing to him but he changed to avoid a repeat.