She makes you beg to be ass fucked

Winny turns her back on you and slips her arms and shoulders out of her white labcoat. She allows the garment to fall from her body and land at her feet, revealing that she is wearing only lingerie beneath it. The small, triangular seat of her black, bikini-cut panties snugly conforms to the pale curves of her shapely ass. Beneath her cheeks, a margin of pale thigh and then her long legs swathed in black stockings. Her upper body is contained, barely, by a black corset with silver finishing. Her cleavage nearly spills out as she twists at the waist and looks back at you.

"I'll make you beg for what I have in store," she says and saunters over to the cabinets, watching your reaction as you follow her swaying hips and generous ass in motion.

She opens a cabinet and takes out a contraption consisting of straps and a blunt hook of dull metal about the size of a curled finger. On the other side of this hook is a glossy black dildo a few inches in length. Winny smiles and steps one leg through the straps, pulling the contraption up her thighs like a pair of mesh panties.

"I worked on this in the technomagic lab for several weeks. I enjoyed testing it with my friend, Miss Meadows. I think I'll enjoy it even more with you."

As she pulls the contraption up the last few inches, she tugs aside the gusset of her panties so that the blunt tip of the metal hook sits just beneath her tender lips. The metal curve flexes and burrows inside her, causing her to gasp. She shivers with stimulation and then moans and runs her fingers over the dildo. To your amazement, the dildo begins to change shape, texture and color, enlarging and stretching until it resembles a living penis. A big, thick, black cock, complete with dangling testicles that fall from the base of the penis.

"Now," says Winny, stepping towards your face and slowly stroking the impossibly real cock jutting from her waist, "beg me for it. Beg me to fuck your arse with this."

"Go to hell," you say, your voice rough from screaming.

Winny smiles, crossing from your line of vision slowly, her grotesquely lifelike cock bouncing with each hip-swinging step she takes. You cannot move your head in the milking stand to follow her as she moves along your flank. You know because she trails her fingers across your side, over your back and to the gentle curve of your ass.

"Beg me," she repeats from behind you.

"Fuck y-"

Agony explodes from your neck through every muscle in your body. The elctricity crackles invisibly across your skin in burning waves and you flex involuntarily in the restraints as Winny delivers a lingering shock. Finally, she releases you and you sag, panting and drooling in the restraints of the milking stand.

"Beg me," she repeats.

"Please," you manage, "go fuck yourself."

This time the shock is so powerful you momentarily pass out. You awaken still in the throes of the horrifying pain, electricity twisting your muscles as you strain against the violent ****. Winny releases the button and you sag bonelessly into the milking stand.

"I can do this until you are driven mad with pain," says Winny. "Now, beg for it. Beg for my lovely cock up your arse."

You wish you were stronger. You wish you could deny her the pleasure of your submission, but you know you are beaten. The pain of the collar is to intense and totally inescapable. You blink tears and dripping sweat from your eyes and slowly lift your head.

"Please," you mumble.

"I can't hear you!" says Winny and she punctuates it with a hard smack to your ass. After the agony of the collar, the smack on your quivering ass hardly registers.

"Please," you cry, anguished by your surrender. "Please fuck my ass! I'm begging you! Please, Winny!"

The heartless harlot seizes your hips just past the **** onions of your ass and she jams the hard head of her freakish cock into your crack. Winny's wizardly willy presses against your pucker and, with a thrust, skewers your unsuspecting anus, pushing up your ass with no lubrication. You cry out as your colon is crammed with ten hard inches, hot and throbbing and as real as any man's cock.

"Oh yes," laughs Winny. "Your hungry arse just swallowed it up. I can feel it you know. Give me a squeeze."

You work your tortured ring around the fat shaft filling your ass. Winny moans in appreciation and you the demented dildo's heavy balls jiggle against your cunt. She withdraws slowly, inch-by-inch emerging from your stretched shithole, until just the bulging head is buried up your ass. With a laugh she drives forward, ramming you full of her cock once more, slapping against your cheeks so hard you sway in the milking stand.

"Now it's time you had a proper rogering," she says, tightening her grip on your waist. "If it helps you enjoy, you can pretend this is a horrible, warty monster's cock up your bum."

She proceeds to fuck your ass hard, rough and fast, driving her hard cock in and out and pummeling your pouting peach with her dangling cumsack. Her words were intended to mock you, but you heed them, picturing yourself being mounted by a scaly, reptilian beast, its pink prick fucking your ass in a growing frenzy. Winny's thrusting intensifies. Her huge cock feels bigger by the moment, and her her long strokes are now lubed with a steady flow of precum.

"Take it, you little monster-fucking trollop," laughs Winny, pounding your stretched hole, hunching over you and roughly yanking your hair. "I'll breed you until you're insane. I'll breed you until you don't even recognize your sister. Is that what you want?"

"Y-yes," you moan as her thighs slap loudly against your ass and her thrusting fuckmeat drives in and out of your ass.

"Aaaah!" Winny cries loudly and her shuddering shaft unleashes a hot gushing river of cum up your tenderized asshole. You can feel her dick throbbing inside you, twitching at your sphincter, basting your bowels with the freakish spunk that fills those testicles. "Oh god your arse is good. No wonder the monsters...unnhhh...love it."

She collapses over your back, sweaty, breasts spilling from her corset across your shoulders. Her huge cock is still twitching inside you, drooling its last spunk down into your ass. The dildo slowly shrivels and retreats as Winny catches her breath. The cock slips from your ass, leaving your little hole raw and gaped and leaking warm cum over your aching cunt.

"You're ready." Winny's breath is hot against your ear. She gathers your hair up and pulls it to one side, licking your earlobe and nibbling. "Tonight I breed you with your first monster."

She leaves you with a last kiss on your ass cheek, jangling the remote for your shock collar as she drops it into her pocket. Dressed, she departs, sending in the orderlies to get you cleaned up and ready for your breeding. They manhandle you out of the milking stand and hose you off in the showers. The fat greasy one from before molests your tits, but goes no further.

After a long, abrasive cleaning you are brought into a large pit covered in white tiles. There is a drain in the center of the room. Above you are one-way windows facing down into the tiled pit. You are given no food or clothing. Soaking wet, you curl up on the floor and shiver, wondering what monster Winny is about to inflict upon you.