Tell her about your fantasies, call her Xyl

"Honestly, Xyl, I've liked the idea of being an Arachne's **** for a couple of years now. I once visited an Arachne village with a trade delegation, and after seeing the slaves, the idea of being stuffed full of eggs and ordered around gave me wet dreams for months. I suspected that it probably wouldn't be as fun to live as it would be to fantasise, but I have yet to find anything to complain about."

She blinks, looking at you with a slightly confused look on her face. "You are actually happy to be my ****?"

"I'm certainly not unhappy, Xyl."

"And yet you accepted my offer to use my name? Surely if you wanted to experience a ****'s life, you would have refused."

"It clearly made you uncomfortable when I called you Mistress," you reply. "A good **** doesn't make their owner uncomfortable every time they open their mouth. Your mother said you want me to like you, but I want you to like me as well."

She looks deeply touched by that sentiment, even if she is still a bit confused.