I've noticed that I say Yes Sir alot now. ALOT! I've also noticed that Yes Sir is said with many different meanings.
I've said Yes Sir in the normal sense of an affirmative answer to a question. "Are you naked?" "Yes Sir."
I've said Yes Sir in response to a statement that really doesn't need my affirmation to be afforded validity because they are statements of Sir's preference and stand alone as that. "I like you being naked for me." "Yes Sir." I'm not really sure why I feel the need to respond to these statements other than to acknowledge that I understand Sir will have what he wants.
I've said Yes Sir to show submission or acknowledgement. "You did not upset me." "Yes Sir." This "Yes Sir" is accompanied by a lowering the eyes, or a bowing of my head. This one is pure acceptance of what Sir says.
I've said Yes Sir to questions to show my desire. "Are you ready to begin?" "Yes Sir." This "Yes Sir" is usually preceded by a moan or a whimper.
I've said Yes Sir to show willingness to serve and give Sir what he wants. "Cum for me," or "Give me what I want." "Yes Sir." This one is not quiet. This one is accompanied by loud moans or strong whimpers. This one is screamed in the moments of passion.
I've said Yes Sir in response to Sir's desires. "I want to lie next to you and cuddle." "Yes Sir." This one is normally preceded by a soft moan. It conveys my mutual desire.
I'm sure there are more. Many, many more. But they each of their own nuances. Their own intonation.
Their own unique moments of expression. Their own separate meanings and acknowledgements.