"Sure!" Okay but that means he needs to come up with something clever now, which is not really his strong suit. Ancestral fae would have been good because of... well, it would be like the other word, and also mean he doesn't have to think of anything clever, but he can't mention that now since she clearly doesn't want it. (Right? No, she said so! Not worth bringing up and making him look foolish or like he's not listening.) "Well..." he really has trouble coming up with anything sensible for himself to say that doesn't sound like he's being a dork. 'Let's do this' or 'are you ready' or wow, 'sex time now' (that one is horrible what is he thinking) are all just not good. But he can imagine Rosy's responses, and, well, he blushes. "I... I'm really not sure what I should say" because all of his ideas are bad and awful "but um, you could say something like 'of course, um, Master.'" He blushes more, having said it (approximately) how he imagined Rosy saying it. "Or, wait, actually, maybe that won't always work because you um, won't always be my, um, slave, right?" Even more blushing. "So it could be sir or we could come up with something else I guess, I don't know." He should have thought it through, damnit! And now he still looks foolish.