Ask her to take off her top

You decide to go for broke and ask for whatever you want. Before you come in her mouth.

"Kuniko, this feels amazing. It would be even hotter for me if you took off your top. I would LOVE to see you breasts."

Kuniko leans back, a little bit of your precum on her lower lip. She thinks about it, and then shakes her head.

"Maybe," she says, "but I think I'd like to get keep my shirt on. Thank you for sharing me how to do this, though. Do you want me to continue, or should we let Sophie try?"

"Oh," you say disappointed, "That's ok, I guess. Would you like to see what it's like for me to penetrate your vagina with my penis?"

"Intercourse?" She asks, "No thank you, I just wanted to help Sophie."

She smiles and turns to her red-headed friend. "Do you want to try sucking on him now?"

Sophie shakes her head. "I'm too nervous, but...I guess I could take my top off? Joe, do you think it would be...hot for you if I took off my top while Kuniko sucked on you?"

Seeing this shy redhead offer to take her top off is an incredible turn-on. "Yes, Sophie, of course. Especially if you got close enough for me to really see you."

She and Kuniko lock eyes for a moment, and Kuniko nods and moves back towards your cock. She takes your shaft in her hand, but doesn't begin pumping yet. She watches Sophie, waiting.