Turn around and spread your cheeks.

"Well, I DID spend how many months railing your ass," you say, as you turn and bend over the bed, reaching back to part your buttocks. "guess it's only fair."

She grins and claps her hands, bouncing up and down, making both her breasts and her obscene strapon gyrate wildly. "Yay! Don't look so scared, as you just pointed out, I've taken that big ol' locked up dick of yours in my ass how many times? And I've come at least once... EVERY. SINGLE. TIME. and usually two or three times. I don't even have a prostate like you do to make it special, either! You were REALLY good at it back when you were allowed to penetrate anyone for sex." Still a huge grin on her face. "And now I know why you were so obsessed with butt sex. You knew your ass was your real sex organ!"

"Hey, I don't know about..."

"We're going to have so much FUN when we get to sissifying you! You always had the best taste in 'classy slut' fashion! I always felt so sexy and glamorous in those outfits you'd put me in, and soon you'll be picking both our outfits!"

The whole time she was talking, she had slathered coconut oil on the lurid pink appendage, then unceremoniously shoved her middle and ring fingers up your ass and was rubbing your distended scrotum and alternately pressing your perineum against those fingers, demonstrating that prostate she had been discussing. The pleasure of her prostate massage had robbed you of your ability to speak as your locked cock strained against its cheap plastic prison, and was running a steady stream of precum. You didn't even try to protest as she hauled her fingers out and shoved almost half of that insanely huge rubber pecker in one thrust, backing out and thrusting a little more back in each time. You actually felt an incredible pressure and radiating pleasure centered behind your balls and spreading out through your thighs and abdomen, your poor cock straining painfully to get erect, then that seed behind your balls exploded, the feeling of fullness in your ass and the rush of the explosion jetting through your penis. The release of that fluid cleared your mind somewhat, but the underlying horniness remained.

She kissed you thoroughly, the love shining in her eyes easing the humiliation of what has just happened. "Sissy's first anal orgasm!" She grinned at you. "Now for presents!"