In Victorian times girls discovered masturbating were often subject to exemplary corporal punishment, as discussed in detail here. Nevertheless, the girls reformatory was, of course, a hotbed of female masturbation.
The younger girls were satisfied with rubbing their swollen clitoris but the older ones, used to regular intercourse outside, craved penetration and hence the dildo. Unable to smuggle in such a thing because of detailed inspection on arrival, the most beautiful inmates would get one from a member of staff in exchange for sexual favors and pass it around the dormitory at night.
You can imagine how eagerly each girl would wait for her turn, stroking her clitoris and listening to the muffled cries of pleasure from the girl using the forbidden item. Then it would be passed on, slippery and dripping, as each girl satisfied herself on it in turn. You can be sure it would do the rounds several times each night.
But inevitably some girls were caught and could expect no mercy. The reformatory strap was the usual instrument of punishment. Read on and enjoy.

Eve heard the crack of the reformatory strap before she felt it. The pain itself took a split second to register, and when it did it started at the edges, as if someone had branded a large square onto her big backside. Then the pain began to radiate inward, and Eve realized that it was the outline of the strap, which had indeed branded a perfect rectangle onto her dreadfully exposed fanny.

Eve opened her mouth to yell just as the next stroke landed.

Instead of screaming, Eve gulped air as the second stroke crackled across her bottom. The stroke landed directly below the first and Eve could feel the pain line from the lower half of the first stroke actually touching the pain line from the upper half of the second.

The overlap was miniscule, but it was agonizing. Eve realized that the Master was actually “painting” her bottom, laying on the strokes with surgical precision. Although Eve felt oddly relieved to be in experienced hands, she knew the price she would pay for being strapped by a master craftsman. The Master knew how to make a strapping excruciating, and Eve would pay the full price for her misdeeds.

As the pain of the second stroke subsided Eve was struck by an altogether different feeling. The impact had caused her hips to rock forward slightly, which caused her most intimate area to rub against the leather padding of the bench. The sensation was undeniably wonderful, and to Eve, who was already hot and bothered from the humiliating forced striptease she had performed for Nigel and her other ‘admirers’, most welcome.

Eve pushed her bottom forward slightly, savoring the friction of the spanking bench as she rubbed herself in her own juices.

[The stimulation offered by the punishment bench to a masturbatrix like Eve has been commented upon before.]

“Now, now, Eve,” the Master warned, tapping her bare fanny with the wicked strap for emphasis. “We’ll tolerate no false modesty from you. Your fanny must be raised high and well spread so your bare cheeks and naughty crack can be properly punished. You’ve been sentenced to a genuine reformatory whipping, and that is precisely what you’re going to get.”

Eve was happy to comply since obedience meant scooting her backside across the leather and into position. The Master’s humiliating command allowed the naughty vixen to enjoy the most deliciously juicy rub imaginable under the guise of “obedience.”

Eve sighed with pleasure as she squeezed the leather between her thighs and raised her backside up and out. This action caused a wonderful, delightful friction, and Eve savored the sensation.

Unfortunately, the pleasurable motion also caused Eve’s rear cheeks to separate and exposed a portion of Eve’s anatomy that no proper lady would ever show.

“I can see her rear port hole!”

“Disgusting!”

“Smile. She’s winking at you!”

Eve was painfully aware of her exposure, and the snickers and laughter as this most private portion of her bottom was revealed, but it felt too good to stop…

She craned her neck slightly and caught Nigel Priggs, disgusting pig that he was, leaning in for a closer look, his trousers bulging.

Eve did not care. The pleasure was too intense. In spite of her humiliation she raised her bottom higher, ostensibly to obey, but in reality to juice herself against the sumptuous leather. Eve spasmed with pleasure.

Eve’s impending climax was cut short as the Master’s voice shocked her back into reality.

“That’s it, Eve…arch your fanny straight up. You’ve earned a good thrashing, and with your fanny cheeks split this next stroke will be make you sing!”

Eve’s eyes turned into saucers as she realized too late the price for her pleasure. She tried to clench, but the strap was already whistling through the air, and Eve’s bottom cheeks were split high and wide…

Eve had polished the strap until the leather was as smooth and supple as butter, and once again her diligence worked to her detriment. The sinuous strap snaked into the crack of her bottom, eliciting a howl from Eve that rang to the rafters!

The Master smiled; bullseye! For the next month, whether standing, walking, or sitting, whenever Eve’s bottom cheeks brushed together she would remember her shameful discipline.

As Eve wailed her 22-year-old stepmother Brittany laughed out loud. Her snotty, prissy stepdaughter was getting it but good, and if Brittany had her way this punishment would be the first of many. Eve’s smug, condescending attitude infuriated her, and she was determined to see Eve stripped of her dignity much as the strap had skinned her inner cheeks.

However Sabrina found she was enjoying the punishment, much to her amazement. As the razor strap did its wicked work Sabrina found herself arching her neck for a better view and squeezing her thighs together. The tingle between her legs was quite pleasant, and Sabrina wondered if her undercover assignment might give her the opportunity to witness other girl’s punishments.

Eve reacted to her punishment in the only way possible. To ease the awful smart between her cheeks, Eve jerked her bottom forward, then back, then forward again.

The audience chuckled as the squirming, bucking Eve tried to “rub out” the sting, but Brittany and the frowning Master quickly realized her true motivation.

“Stop the punishment!” Brittany said, her voice cutting through the air like a whip, “The little slut is juicing herself!”

The spanking bench contained retractable “pedals” which could be snapped out from the base at a moments notice. The tiny foot stands gave the culprit a way to stand, or at least arch her bottom upright and spread her legs wide, in case a sudden “contraband search” was deemed necessary by the powers that be.

The “contraband” the Master and Brittany were searching for were not drugs or weapons but Eve’s natural syrup, but the mechanics of the search was the same. The bench’s foot-stands were quickly snapped into place. Eve’s feet were quickly guided into the correct position and the order was given for her to raise her hips

Eve hesitated. Her legs were spread wide, but at least her privates were pressed tightly against the bench. If she raised herself up her bottom would be in the air, and the men in the audience would see everything they wished to see.

Two smart SPANKS! Across her exposed bottom reminded Eve that her modesty was of no concern. Reluctantly, Eve raised her hips and opened herself like a beautiful, bashful flower.

The bench and Eve’s exposed twat positively glistened with her juices, and it was obvious to everyone that Eve had in fact been using her ride on the spanking bench to pleasure herself. Yet despite the indisputable evidence the Master insisted on a manual search of the crime scene.

Brittany smiled as the Master ran his hand over the wet leather of the spanking bench before bringing his pudgy fingers up to his nose. It was girl cream, no doubt about it. The Master turned to Brittany and nodded, as if his sage investigation had uncovered the smoking gun.

Now that Eve was at her mercy, Brittany wouldn’t miss the chance to pile on. “Perhaps you should check the source,” she suggested slyly.

The Master didn’t have to be asked twice. Eve gasped as the Master searched her well lubricated, gaping sex inside and out, and rubbed her until the juices flowed freely. After all, if juicing Eve didn’t prove that she was juicing herself, nothing would.

The Master’s inspection was repeated by Professor Winters, and then by Nigel, until it was determined that he really had no official capacity whatsoever and should take his seat.

Eve was ordered to remain in position with her bottom raised and her legs spread wide as the Master moved to the corner of the room with Brittany to discuss her fate. Regrettably this position left poor Eve shamefully exposed to both the peering eyes and cruel remarks of the audience.

The fact that many of the men still had their hands in their pockets, and many of the women had been squeezing their thighs together since Eve had begun to strip, was wholly irrelevant. Eve was a randy slut, and her masturbatory habits were an outrage to public decency. Public opinion was both harsh and swift.

“She’s dripping like a faucet!”

“Look at her twitch. It’s like she’s ready to take on an army.”

“Disgusting! I can smell the little tart from here!”

“What do you think they’ll do with her?”

“If it were up to me, I’d use the pony whip!” (Eve’s cheeks flinched at the thought, and several men in the audience laughed.)

“What good would the whip do? The little slut would probably enjoy it.”

“Can you imagine having a piece of tail like that waiting for you at home every night?”

“Yeah, she’s the perfect woman. She knows how to act in public, but she’s a ho in the bedroom!”

Eve blushed and fidgeted as she listened to the audience discuss her “lickable thighs”, “luscious ass”, “tight little bumhole” and “randy twat,” which one thoughtful observer compared to “a delicately formed oyster.”

Eve looked towards the corner where the Master, Professor Winters, Miss Rawlings, and Brittany adjudicated her fate. Eve couldn’t hear what they were saying, but Brittany was talking and Miss Rawlings was grinning, which was an awful combination.

At last the conclave ended. Brittany, smiling ear to ear, stood next to Eve as the Master pronounced her sentence. “Because of her outrageous conduct during her punishment, Eve’s stepmother Brittany has suggested that we dispense with the strapping…”

There were shouts of disappointment from the crowd, but Eve’s heart soared. She was saved! But why had her hated stepmother rescued her, and why was Brittany grinning?

The remainder of the Master’s pronouncement answered both questions. “…dispense with the strapping, and administer the remainder of Eve’s punishment with the birch.”

Laughter, followed by applause! Eve couldn’t believe it. The birch! It had to be a mistake!

Eve thought the news couldn’t be worse, but she was wrong.

“In order to make sure this randy strumpet feels the full effect of the punishment she so richly deserves, Brittany has generously volunteered to complete the shameful act which has distracted this vixen so. Brittany, if you will?”

At first, Eve didn’t even understand. But the meaning became clear as the smiling Brittany teasingly ran her fingers up and down the lips of Eve’s exposed sex.

Brittany began slowly but quickly picked up the pace. “I’m standing to one side, dear, so everyone can have a clear view,” Brittany said, in a tone so calm and casual that it reminded Eve of a master chef on a cooking show. “After all, everyone will need to see your little hole twitch when you come, so we know you’re not faking it.”

Eve gasped and squirmed under Brittany’s skillful caress. She was soon panting too hard to speak, so instead turned her head back and pleaded for mercy with her eyes. There was none to be found. Brittany drove Eve on mercilessly, with a twinkle in her eye, a broad smile on her face, and a thumb that knew precisely where naughty girls liked to be rubbed.

“Disgusting! And to think they were actually going to make her a Professor!”

“She belongs in a brothel.”

“Or an alley. 25 pesos a roll.”

“Look at her face. It almost seems like she’s in pain.”

“No, the pain will come later, when they skin that wiggling ass of hers!”

“Yes, she’d better enjoy herself now. Play now, pay later.”

Eve knew that she would indeed pay later, but that didn’t make her pleasure now any less intense. Despite the humiliating commentary, or perhaps because of it, Eve was soon rocking her hips through the most shattering orgasm of her life. As Brittany predicted Eve’s soggy hole twitched and spasmed, much to the audience’s amusement.

But even after Eve’s orgasm finally subsided, Brittany did not stop. Her fingers kept working their way in and out, and her thumb kept rubbing…rubbing…rubbing.

Eve panted like a dog. “Please, she gasped. “Not…not again. I can’t take it!”

But Eve had to take it, and soon was coming again. A number of the women watched with dismay as the secrets of female self-pleasure were revealed to prying male eyes.

“Little slut. She deserves to have her fanny skinned. Humping that woman’s hand like that!”

“Yes, if she were my daughter, she’d feel like she’d sat on a hotplate.”

Eve had no say in what was happening, but that technical detail was lost in the moral righteousness of the moment. The men chuckled and the women scowled as Eve’s exposed sex puckered and writhed through her second orgasm.

Eve lay limp as a rag doll. However when she bent her knees to collapse onto the horse her exhaustion was rewarded by a sharp SLAP! across her freshly strapped fanny cheeks.

“Stand up straight, you little slut, legs apart,” Brittany said crisply. “I’m not finished yet.”

Eve straightened up, her thighs parted, and Brittany’s fingers resumed their wicked work.

Only Eve’s little hole twitched its way through its third orgasm Eve was finally allowed to rest. She lay limp across her bench, bushed in every sense of the word, totally oblivious to the activity behind her.

It wasn’t until Eve felt the drops of brine hitting her in the face, and spied the smiling Miss Rawlings shaking out the bundled birch rod that she realized her time had come.

Eve watched in horror as the beaming Miss Rawlings handed Professor Winters the bundled rod. “Since I’m your faculty advisor, the Master thought it appropriate for me to administer this phase of your punishment,” Professor Winters explained. “Have you ever been birched, Eve? No? Well, then you’re really in for a treat.”

SWISH! THWACK!

Eve’s post-coital bliss ended abruptly as the birch found its mark. Eve felt as if a thousand hornets had stung her bottom simultaneously, and she let out a sound that was half scream, and half yelp. A few twigs broke off and flew past her head, landing on the floor in front of her.

The woman in the audience who had been angered by Eve’s wantonness voiced their enthusiastic approval.

“That’s more like it!”

“Yes, make the little slut’s bottom dance.”

The pain was indescribable, and Eve’s head buzzed. As she watched the smiling Professor Winters shake out the birch rod in preparation for the next stroke Eve realized the terrible power a teacher has over a student.

Eve was a smart, but she had a sharp tongue and little patience with students who displeased her. In that moment, she vowed to rededicate her heart and soul to teaching, and never abuse the trust that had been given her.

Tap-tap-tap!

“Please,” Eve said, gasping for air. “I’m sorry for trying to escape. I’m sorry for being so…so horny! I’m sorry I’m a…a naughty stinky finger. Please! You have to stop!”

“Stop?” Professor Winters said, chuckling. “We’re just starting. You have a long lesson ahead of you, young lady!”

Eve’s head swarmed. “No, wait. I can’t do this. Tell Sabrina I’ve changed my mind. Tell her…”

Eve’s final, desperate escape hatch was kicked shut as Miss Rawlings slipped a leather gag into her mouth. “Now, now, dear, we don’t want you to damage those pretty teeth with a lot of gnashing,” she purred as she buckled the gag behind Eve’s head. “Now we can make sure that you feel each and every stroke!”

Miss Rawlings smiled indulgently. The gag rendered Eve’s frantic explanation unintelligible. To all the world Eve looked like a foolish nitwit, babbling frantic nonsense as her Professor flexed the switch.

Eve realized to her horror there was no way out. Eve hoped that Professor Winters would see the panic in her eyes. She hoped that Detective Duncan would halt the punishment. In her wild desperation she even dreamed that her beloved father would burst in through the doors and save her from this gross injustice.

The response Eve received, however, was the response she dreaded most. Professor Winters rubbed the bristling, wicked birch switch against her bottom, and chuckled softly. “Do you remember your sexual harassment lawsuit, Eve? Did it make you feel powerful? Now, you’re going to find out what true power is all about.”

As she realized that she was going to be soundly birched Eve experienced what could only be described as a panic attack. Rivulets of sweat poured down her face. Her heart raced. She gasped for air through her gag.

The second stroke exploded across her bottom; it was needles of fire. However Eve only felt it for an instant, as her panic finally overtook her.