Lady Scarlet wanted to undergo a cosmetic procedure and she wanted it to be perfect. So she had to make sure that he was in the right frame of mind to do it and he had to be at his best as well as there was no going back. And that is how the mistress turned to domination to send him a message and he got it loud and clear.
This mistress had a new assistant but he was late for work and she did not like such behavior as it showed that he did not take his work seriously. So the mistress chose to give him a little incentive to get to work early and that was in the form of turning him into a foot slave and having him lick her feet, her socks and her shoes before she felt it was enough.