Yes. Without buts

"If you wanted? Sure" you answer, grinning to her reaction. Surely she's expecting that you'll back off, but you are not one who loses games like this.

"So you admit that you are a pervert?" She asks mocking shock.

"Sara what's wrong with sex between relatives in a world full of contraceptives? Of course I'd fuck you if you offered. It's not like we are talking about marrying and having kids." You continue to bluff, expecting that she will run out of her questions and you'll both laugh about it.

"So, only my lack of willingness stops you?" Sara doesn't plan to lose the game and prepares the next kinky question. "Or is its fear? Would you **** me if you knew that you would never get punished for it?"

"Hey, Sara. It's not funny, anymore" You protest "How could you say that? I love you, you are my friend. Who do you think I am?"

"Oh, you wouldn't take me by **** because you care about me. Good to know." Sara grins "Would you **** a complete stranger given the chance?"

That question hit you hard. She guessed your most intimate fantasies. "No... Yes... I don't know. If she was hot and helpless and... I would like to be able to resist but I am far from sure that I could. It's like having a chance to steal a million dollars, really hard to resist" you answer, lowering your gaze.