Some fisting

You hear Sarah pick something from a rack of some kind. You then feel her hands spreading your buttcheeks and twirling the buttplug in your ass. You moan as the turns it this way and that before slowly pulling it out and dropping it on the floor.

You hear latex being pulled on and realise that she´s putting on a glove. She´s probably gonna fist you!
Soon enough you feel one, then two, three and finally four fingers up your ass. Your sphincter is stretched and aches to relax.

But Mistress Sarah doesn´t care about that. After adding a bit more lube and some more coaxing, her fist is almost sucked into your ass. After all, when the knuckles are in its shaped like a buttplugg.
You feel her fingers wiggle around inside you until they find your prostate and give it a painful squeeze, making you cry out.

"There we are, now to really make you a bitch"

Sarah painfully yanks out her hand, leaving your ass to feel stretched open and empty at the same time. Soon however, your feel something huge pressing against your sphincter. It´s even a bit wider than sarah´s hand!

Stretched as you are, resistance is futile. In it goes in a nice slow pace. Finally you feel Sarahs hips pressing against your after what feel like an eternity.

"Hows that Cockslut? 14 inches up your ass!"

14 inches? Holy shit, no wonder it feels like a baseball bat up your ass!
Sarah removes the ring gag and presses a big knot of latex between your lips. You´re a bit confused by all this, well, as much as can be with a huge dildo up your ass in a dungeon.

"That´s my glove in your mouth. Bet it tastes like your slutty ass!"

You feel her pull back until just the tip of the rubber cock is in. Then she rams it in full ****, making you cry out, muffled by the gag. She keeps this up, fucking you like a jackhammer until you think you´re gonna black out.