My wife appeared more nervous than usual in her submissive role as she presented herself for my inspection. It was not that she feared I would find fault in her schoolgirl uniform of black shoes, white ankle socks, short blue skirt, white blouse and tie. This was exactly how I, her Master, had decreed she should dress for the evening. Her blonde hair was drawn back in a ponytail and she wore no makeup, which lent her a look of blue eyed nubile innocence.

Her concern related to the exact nature of the present she was shortly to receive for her twenty-fourth birthday. I had refused to divulge any details, other than promising that my beloved slave could expect a most unusual and totally appropriate surprise. Earlier that day, she had earned twelve strokes of the cane on her bare backside for pleading with me to tell her more about her present. The punishment would have been far more severe had I not been sparing her for what lay ahead.

As nine o'clock approached, I myself grew more expectant. During our three years of marriage, Claire and I had played a wide variety of slave/Master games, but tonight would bring a whole new dimension to our relationship. She probably did not even remember the secret fantasy she had confessed to me over a year previously and I had studiously avoided reminding her, lest she suspect the birthday treat I had so carefully planned. I was confident she would enjoy it every bit as much as me.

Shortly after nine the doorbell chimed. I rose to answer it, ordering her to remain standing in the centre of the room.

Standing on the doorstep was a tall and slender vision in knee high boots and figure hugging black leather, black hair tightly cropped. pale, high cheek-boned features aggressively set.

"Mistress Ava," I smiled. "Come in. Your slave awaits you."

"Is she expecting me?" she asked, stepping into the hall.

I shook my head. "Believe me, you're the last thing she's expecting for her birthday."

I escorted her through to the living room, where Claire was waiting obediently, hands by her sides. Had she been a cartoon character, her eyes would have popped out on springs at the sight of the leather-clad dominatrix.

"You must be Claire," the Mistress said, roaming over her with her dark eyes.

"Wh ... who is this woman?" my shocked wife demanded.

"This woman is your Mistress for the evening," I replied. "You will obey, without question, her every command. She has my permission to do whatever she wants with you. You may..."

"I'm in charge of this slut now," Ava interrupted sharply, throwing me a frosty glare. "I believe you have a video camera to attend to."

I blushed, feeling as though I were the slave. I could not have hired a more intimidating Mistress for my wife had I spent half a lifetime searching. "Er, yes, of course," I stammered, before hurrying upstairs.

When I returned a few minutes later, camcorder already running, Claire was on her knees and gazing up at her fearsome Mistress through terrified eyes. I had feared she might require some firm persuasion before submitting to her, but she was obviously far from reluctant to enter into the spirit of the game.

"Let's get the rules clear from the start," Ava rasped, cupping Claire's chin with a leather gloved hand. "You will speak only when spoken to and address me at all times as Mistress. I am your superior in every way and my word is law. Do you understand, slut slave?"

"Yes," she whimpered.

Ava tutted. "Forgotten your manners already! I think it's time I was shown to the dungeon."

Claire started to rise, but her Mistress snarled at her to remain on her knees. She could crawl to the dungeon like the miserable dog bitch she was. My wife cast a pleading look in my direction, though knowing I had not the slightest intention of intervening on her behalf. My one and only role for the remainder of the evening was that of cameraman. She was in the hands of Mistress Ava and could expect no mercy.

Claire crawled out into the hall and then up the stairs, her Mistress following close behind, feasting her eyes on her nicely rounded rear view. I was certain the dominatrix was a lesbian, despite the fact that she specialised in dominating clients of both sexes. In my search for a suitable Mistress, I had contacted over a dozen such women. She had been the only one who seemed not only willing to accept my cash, but positively eager to provide a sado-service for my wife.

I had invested a great deal of time and money converting one of the spare bedrooms into a fully equipped dungeon. It was well stocked with all the equipment necessary for the training and punishment of a slave and Claire worshipped every inch of the purple walled chamber. It was our private temple and Ava its first guest. If tonight went as well as I hoped, she would not be the last.

She carefully inspected the facilities and equipment, while the slave knelt in the centre of the dungeon, visibly trembling. Following several minutes of contemplation, Ava selected a riding crop from the rack of punishment tools on one wall. Claire flinched as she cracked it against her right boot.

"Stand up, slave," she barked. When Claire hesitated, she struck her boot with the crop again. "I said stand up, you stupid slut! For every time I'm forced to repeat myself, I shall double your punishments That's it. Now, pull your knickers down to your knees and bend over. Hurry up! I am not a patient woman."

Tears of humiliation brimmed in my wife's eyes as she bent over and touched her toes, white cotton panties stretched between her knees, short skirt riding up over her hips. The pattern of the caning I had earlier administered was criss-crossed pink on her milky rear cheeks. Ava hiked her skirt up higher, ensuring her backside was totally exposed, then stepped to one side and drew back the riding crop.

The savage lash exploded across Claire's round rear with a sound like a gunshot. She responded with a shriek of pain. The Mistress waited a few seconds, then struck her again, with even greater severity. For some reason, I had expected her to be slightly more restrained, perhaps out of sympathy with a fellow female. As she proceeded to unleash a savage salvo with the riding crop, I realised I had worried needlessly. Ava was a first class sadist, with not the slightest inhibition.

I lost count of the number of times she struck her, before finally laying down the riding crop. Both buttocks burned a savage shade of crimson, only a few ragged strips of pale flesh remaining. Streaks of a similar shade were printed on the backs of her thighs.

"Well, slave, what do you say?" Ava demanded.

"Th ... thank you, Mi ... Mistress," Claire sobbed.

She was given no time to recover from her punishment. Ava ordered her to pull up her knickers, then stand up straight, arms raised high above her head. The Mistress undid the top two buttons of her blouse, then ripped it open. Underneath, Claire was wearing a lacy white bra that allowed a generous portion of her ample breasts to remain visible.

"Nice tits," Ava mused, pinching the bulge of her left nipple between thumb and forefinger.

"Thank you, Mistress," Claire responded.

"Did I permit you to speak?" Ava demanded in a steely voice.

"No, Mistress. But ..."

"Shut your mouth, slut," she spat. "It seems an immediate reminder of your manners is required. First, you must be tied up."

A set of studded thick leather manacles dangled from the ceiling. The chains were just the right length for my wife to be forced to stand on her toes when her wrists were securely clamped. The entire dungeon had been designed, after all, just for her. Once she was in position, Ava placed a steel spreader bar between her feet, pulled down her socks and strapped an end to either ankle. She adjusted the width of the bar until Claire's legs were forced far enough apart for her muscles to ache.

"That's better," Ava announced. "Now, I can begin punishing you in earnest."

Rather than waste time on the niceties of unclasping Claire's bra, she tugged down the lace cups and roughly worked both breasts free of their confines. She removed her gloves and smacked her globes several times with the palm of her right hand. Claire's eyes followed her as she walked across to the table where I had laid out a large selection of torture equipment. She probably knew what was coming next, but still paled when her Mistress picked up a pair of silver steel nipple clamps.

A small whimper issued from between her trembling lips as the cold jaws of the clamps bit her stiff brown nipples. For good measure, Ava tweaked both throbbing buds a few times, then returned to the arsenal on the wall and selected a wooden paddle that resembled a table tennis bat. One side was bare polished wood, the other covered with conical studded thick black leather.

Using the studded side of the paddle, she began vigorously whacking Claire's quivering breasts, her efforts being rewarded with repeated high pitched cries of pain. She did not stop until they burned as lividly as the cheeks of her bottom. However, the tit torture was far from finished.

She used a pair of thick leather thongs to bind Claire's breasts, pulling the knots so tight she screamed. Her trussed tits bulged like a pair of crimson balloons. Ava then treated them to twelve strokes apiece with the riding crop, nudging her agony up several notches further.

Having surveyed her handiwork with unconcealed pride, she unbuttoned Claire's skirt and tugged it down. It was too tight to go any further down her splayed legs than just above her knees, but that was quite far enough. Her panties followed.

"Just like a little girl," Ava mused, admiring the smoothly shaven mound of her sex. "But you're no innocent little virgin, are you, slave? Oh no. What you are is a cheap fucking slut. A cock-sucking whore who isn't fit to lick my boots. Isn't that right?"