Mistress Dorothy taunted this guy and told him how weak he was. She was just messing with him to bait him to try and prove to her that he was not weak and in so doing, get a chance to trample him. She wanted to try it but she did not have a slave so that was her best chance of doing it. The guy took the bait and she had fun trampling him.
Mistress Melina did not want to be disturbed by her slave. She had given him firm instructions on what she wanted and she hoped that he would adhere to them. But he did not and she had to punish him. She did it cruelly and forced him to endure her punishment. She hard trampled him and when her friend came to visit her, she also joined in and they trampled him painfully.