This mistress wanted to dominate and she chose to do it when she had time and she could do whatever she wanted. She chose to make this guy lick her socks and do all manner of things. They were random things that came into her mind. His work was to do what she asked or rather ordered. The mistress did not care about what he felt or did not feel.
Mistress Djerdlid was not going to let anyone mess with her. She had to pass an important point across to her slave and when she noticed that he was not paying proper attention, she had to punish him and she did so with her stinky and dirty socks. He had to lick her socks and do all manner of things before she felt that he had gotten the message she wanted him to get.