Depending about how you feel about them BDSM honorifics are boring, artifical, complicated, arousing. (I vote for all of the above.)
Devastating Yet Inconsequential has found a playful use for the femdom favorite “Mistress:”
To deal with this last thing, we have introduced a new protocol, which is that he is to respond with “Yes, Mistress” in response to an instruction and never in response to a request for a favor. If he guesses wrong I’ll correct him (not to be mean, but to help make sure he knows what’s going on). The truth is that almost everything I ask of him is either explicitly an order, or something I’m happy to have interpreted that way. (An exception would be something like “Would you please hold me? I feel like I’m going to cry.”