The following is a sexy short story I wrote after seeing a number of stories about men with bionic penises. Yes, by the way, this story includes a bionic penis. Enjoy!

It was another cold, dreary night on the outskirts of Centerfield University. For most people, it was a perfect excuse to stay indoors, curl up on the touch, and binge watch whatever shows made them forget how cold they were. For Kelly “Roxy” Rindle, those nights had a different meaning. They usually meant she was going to be busy.

“Another storm, another city full of lonely men,” Kelly sighed as she entered a hotel less than an hour after sunset. “I need to start charging a higher premium.”

Making her way through a mostly-empty lobby, not even making eye-contact with the receptionist at the desk, she slipped into the nearest bathroom to fix her appearance. Wearing a heavy coat that covered a low-hanging halter top and skin-tight black pants, Kelly took a moment to recover from the blistering cold. She also had to re-apply her makeup, brush her hair, and apply her lip balm. As an independent escort, she had a brand to maintain.

“I should charge extra for the makeup I have to buy,” Kelly said to her reflection in the mirror. “I’m sure that discount store on campus knows girls like me need it.”

Girls like her – a concept that used to bother her, but had since lost meaning – had an unspoken rule about their illicit line of work at a place like Centerfield. First and foremost, it had to be a choice. Nobody who didn’t choose ever lasted long in the world of sex work, but that choice took on greater relevance for those who escorted as a means to an end.

Centerfield University was one of the most prominent schools in the country, attracting some of the most promising students. Kelly had been one of them and it had been her dream school since her freshman year of high school. She remembered cheering for a half-hour straight when she got accepted. However, getting good grades for four years of high school was the easy part. Paying for it proved much more challenging.

Centerfield University was a top tier school, but it was expensive, even by private school standards. Everyone who didn’t have a scholarship had to work a job or have rich parents who could pay the hefty tuition. Kelly didn’t have rich parents, nor did she have much in terms of college savings. She knew she’d have to work a job if she wanted to attend her dream school. She just didn’t think she’d end up being an escort, although in hindsight, it seemed inevitable.

There were a lot of factors that went into that choice, but she’d made it and had since stopped regretting it. Kelly didn’t dwell on it as she finished applying her balm.

“That should do it,” she said as she put her makeup away. “Time to earn my overpriced tuition.”

Kelly exited the bathroom and briefly checked her phone to see that she still had time. Her first client of the night had scheduled her for a standard-length session. He was a new client and while she usually didn’t see them first, he offered to pay extra and she needed every dollar her former track star body could earn.

That was the second and most frustrating rule of escorts around Centerfield. Anyone who had any desire to graduate with a degree and not be crippled by loan debt had to jump at every opportunity. Sometimes, that involved a scholarship or a well-paying side-job. Sometimes, that involved being an escort.

Centerfield already had a sordid reputation for the number of students working as escorts. Kelly learned shortly after she got into the business that the competition was fierce. Chances were there were other pretty girls serving clients tonight with an unspoken understanding of why students like her had to sell sex to pay the bills. It wasn’t that they had no choice. It was just the easiest, especially for someone who’d started filling out bras earlier than most girls.

Having naturally good looks was just part of what made a good escort, though. They also needed to actually enjoy sex, which Kelly certainly did. Granted, much of that was due to an overly horny ex-boyfriend who had gone to college on the other side of the country, but that experience had done enough to prepare her. She knew how to have sex, how to enjoy it, and how to be sexy. It made for a relatively easy transition into escorting.

Kelly needed easy at the moment, mostly because her first couple years at her dream school had been mired in uncertainty. She thought she knew what she wanted to do when she got accepted. She hoped to study business, get an MBA, and then start her own business one day. Then, she began taking classes and found out that it might not lead to the kind of career she’d hoped. To date, she still hadn’t figured out an alternative.

“I’ll need to justify that tuition soon,” Kelly muttered as she entered the elevator. “At some point, I need an actual dream to go along with my dream school.”

She could already hear her mother berating her for wanting to switch majors. She’d probably be more upset about that than she would if she found out she worked as an escort. Kelly chose not to tell her, opting to handle one difficult issue at a time. Checking her phone, she sat that it was almost time.

“Better save those dreams for later,” she said with more focus. “For now, I need get sexy.”

As the elevator ascended, Kelly adjusted her demeanor in preparation for her client. She let Roxy, the persona she marketed online, take over. Roxy wasn’t concerned about school, tuition, and her future career. She was just a horny young woman who looked good in a thong, loved to fuck, and needed money.

Strangely enough, being Roxy was probably the least complicated part of Kelly life. It didn’t involve complicated life choices. It just involved her taking her clothes off, putting on a sexy face, and having sex with men. It was both easy and lucrative, especially for someone who’d learned she had a sexy side at a young age.

“I am Roxy,” she told her reflection in the elevator door. “Go do your thing!”

A soon as the door opened, Kelly left all those uncertainties behind and made her way down the vacant hall to Room 622. Her client had texted her 15 minute ago, saying he was ready for her. She’d told him she would be there at eight o’clock sharp. As any competent escort knew, time was their second most precious commodity. Kelly made it a point not to waste a second of it, arriving at the door and waiting until the exact second to knock. That was her way of letting her clients know that she was both punctual and dedicated.

“Here we go again,” she said under her breath before embracing her Roxy persona.

Within seconds, the door opened and Kelly got her first glimpse of her new client.

“Good evening,” a man greeted. “I’m Marvin Herbert. Are you, Ms. Roxy?”

“That’s me, hun,” Kelly replied with a curt grin, “and just call me Roxy. That’ll make it easier.”

“I agree. If it helps, you can call me Marv.”

“I’ll call you whatever you want. That’s my job, right?”

“Right…I suppose,” he said sheepishly. “Please, come in, Roxy.”

Nothing seemed out of the ordinary. The Marv seemed friendly and unimposing enough. He didn’t look that much older than her, appearing to be in his early 30s or so. He was no athlete, standing less than six feet tall and having the kind of lanky frame that implied rarely got picked first in gym glass. He was also somewhat pale, wearing black khakis and a dress shirt that most men wore to an office. He reminded her someone who worked in the science department at Centerfield. Those people always dressed like they were going to a dinner party.

His smile and his demeanor didn’t set off any red flags. Feeling assured, Kelly entered the hotel room while Marv closed the door, putting the “do not disturb” sign on the doorknob in the process. She then casually approached the bed, making it a point to shake her hips in a seductive way, hoping to set the mood.

“Thank you for seeing me on such short notice, Roxy,” Marv said after locking the door. “You mentioned you don’t see first-timers, as you call them. Believe it or not, you were the fifth person I contacted in my effort to set this up.”

“I believe it,” Kelly said. “Some girls are extra cautious with newcomers, but I’m willing to get a little daring here and there.”

“And I appreciate that. That’s why I tried to put extra into your uh…gift.”

Kelly noticed his eyes awkwardly shift to the envelope on the nightstand next to the bed. It contained her payment. As per the rules of basic escorting, money was not to be mentioned. It was just supposed to be there in plain sight for her to collect once their business was complete. The man seemed to understand that, but his inexperience in dealing with escorts really showed.

“No need to get nervous,” Kelly told him, now leaning back on her arms and giving him a seductive glance. “Don’t focus on the particulars. Let’s just get extra comfy on this chilly night.”

“I’d like that, Roxy,” Marv said in an oddly intrigued tone, “but there are a few details I’d like to share with you?”

“Oh? What kind?” she asked, wondering what sort of kinky tastes the man had.

“The kind that I hope will show the fruits of all my hard work. If all goes well, you’ll be the first one to experience it directly.”

Kelly, still trying to maintain her Roxy persona, cast the older man a strange look. He still hadn’t set off any red flags, but he was getting close. She didn’t get the impression he was role playing or anything like that. He seemed both serious and excited, although she wasn’t sure it had anything to do with her presence.

As she sat back on the bed, Marv approached her with an eagerness that reminded her of a man who’d just bought a fancy new car. It felt as though her being an escort didn’t even matter to him. It heightened her suspicions, but it also sparked her curiosity.

“You see, I’m a lead researcher at the Centerfield science labs,” Marv went on. “I’ve got two masters degrees, one in biology and one in bioengineering. I’m also working on my PHD.”

“Wow. That’s impressive,” Kelly remarked, “so I may end up calling you Dr. Herbert?”

“If all goes well, you just might at some point,” he said with a humored grin. “For the past five years, I’ve been conducting research on a new generation of medical implants. It’s a growing field with exciting application and I’m not just talking about pacemakers. We’re getting to a point where we can create targeted implants for localized, precise treatment of defective tissues.”

Kelly kept smiling, but almost ended up laughing. Marv sounded way too energetic for someone talking about science, a topic she know or care much about. Even though she’d gotten a B-plus in all her science classes, she had never encountered someone who got so giddy about it. It was kind of cute, but still pretty odd, even by escort standards.

“That sounds fascinating,” Kelly said, pretending to be turned on by it.

“It is!” Marv continued. “I’ve spent the last several years, trying to push things forward faster. I’ve annoyed a few people and I’m told my people skills are average at best, but I’m willing to pay that price for my work.”

“That kind of dedication is admirable, Marv.”

“It’s also the easiest part, unfortunately. I must have done something right because I finally managed to get a prototype built. Unfortunately, making a prototype and testing it are two different things. The process for rat trials, alone, is excruciating and I’d rather not wait that long. Some leaps in science require extra risks and I think this is one of them.”

There was a strange glint in his eye. Kelly had never seen anything like it and for an experienced escort, that was saying something. She ceased being suspicious, no longer suspecting that there was something dangerous at play. She found herself genuinely interested in what the man had to show her.

“But enough talk,” Marv said. “I understand our time is limited so why don’t I show you?”

That glint never left his eye as he stood before her at the foot of the bed, undid the belt buckle on his pants, and pulled them down, along with his boxers. He then stepped out of his dress shoes and took a step back, giving Kelly an unobstructed view of his penis. She tried not to react too strongly, but even an experienced escort took notice when a man just exposed his genitals to a stranger.

Near as she could tell, Marv had a fairly average endowment. Having been an escort for over a year, Kelly had seen all sorts of shapes, sizes, and configurations in male genitalia. Some were more noteworthy than others, but Marv didn’t appear to have any distinguishing features. He seemed very casual about it, which was uncommon for men who didn’t regularly sleep with beautiful women. She still gave him a sexy smile, though, if only to maintain the mood.

“I see,” she said teasingly. “Is this related to your work?”

“Very much so,” Marv affirmed. “I don’t know how big you are on science, but I hope you watch closely. You’re about to witness a true scientific breakthrough!”

With an eager grin and a confident poise, he pressed a button on his watch, which looked like an ordinary watch from a distance. Kelly wasn’t sure what to expect. For all she knew, it could’ve turned him into a werewolf. However, within second of pushing that button, she saw something happen with his penis.

In a sight that defied everything Kelly thought she knew about male anatomy, Marv’s penis went from completely flaccid to fully erect in just a few seconds. It got so hard so quickly, as though it were a light switch. He didn’t touch it or shift his demeanor in any way. He just got hard in a way that would’ve made a male porn star jealous. At that point, she didn’t even have to pretend to be impressed.

“Wow!” Kelly gasped. “What exactly just happened?”

“The culmination of some very dedicated, admittedly kinky research,” Marv answered proudly.

“Um…care to be more specific?” she asked, still processing the sight.

“It would take way too long to go over the technical specs. Simply put, I surgically installed a biomechanical implant into my penis and treated the surrounding tissue with a synthetic substrate of programmable bio matter to facilitate external excitation of specific peripheral nervous responses.”

“That’s…still too technical.”

“Well, in exceedingly unscientific terms, I gave my penis a cybernetic implant. You are looking at, to my knowledge, the first cybernetic penis in history.”

Kelly blinked a few times, needing more than a few moments to process what she’d just heard. She knew what the word cybernetic meant and she knew what a penis was, more so than most young women. The idea of putting them together never even crossed her mind.

It sounded like a joke, one she wouldn’t have even laughed at had she’d not seen what she just saw. The idea that she, a finically-challenged college student who did sex work on the side, was the first woman to ever see a cybernetic penis was pretty jarring. It was also kind of neat…if not intriguing in a kinky sort of way.

“I’m going to be honest with you, Marv. I’m kind of at a loss here,” Kelly said, still trying to process the implications.

“Take all the time you need, Roxy,” said Marv with a humored look on his face, “but in the interest exploring those implications, I should probably show you this too.”

As her mouth hung open in astonishment, the unassuming man pushed another button on his watch. Then, she heard a very low-pitched humming sound that came directly from Marv’s penis. Still standing with the pride of a man who’d just won the Olympics, he took a step forward so that his dick was right in here face.

“Here,” he told her. “Touch it.”

That might have been the most polite request Kelly had ever heard in her time as an escort. She’d never obliged so willingly or eagerly, for that matter. As soon as she placed her hand on the fully-erect member, she felt it vibrating in her hand.

Again, Kelly needed a moment to process the situation. In her hand was a live penis, attached to a man and appearing completely normal from the outside, and it was vibrating. It vibrated with the same subtle, yet noticeable intensity she’d felt in a numerous sex toys. Having owned more than one vibrator in her life, she could tell the difference between cheap and premium vibrations. From the looks of it, Marv invested heavily in quality.

“Wow,” Kelly said as she held his cock in her hand. “I know I said that already, but it’s worth saying again. Wow!”

“Say it as many times as you need to,” Marv told her. “From a scientific perspective, your reaction counts as promising results.

“I’m not entirely sure on my perspective right now. I’m also no scientist, but if I’m making the right connections here…you actually operated on your own dick?”

“Well, I did say that great leaps in science require risk,” he said in a bemused tone. “I figured it would be too difficult to find a man who would agree to such a procedure. So I volunteered myself.”

“That takes an obscene amount of balls!” Kelly said. “Wait, you didn’t operate on those too?”

“No, I didn’t,” he laughed. “The procedure wasn’t as extensive or messy as you think. I won’t say it was comfortable, but a good scientist is willing to endure for his work.”

“I think you’ve officially raised the bar for every scientist in the world.”

“And I’d like to raise it even more,” Marv told her. “To do that, though, I require a more complete test.”

The tone in his voice took on a more sensual subtext. Kelly didn’t need a masters degrees to figure out what he meant by it. She was an escort, last she checked, and she had planned on having sex with him at some point during their session. She just didn’t expect it to take on such a strange new context.

Marv almost seemed anxious after making his request. He obviously didn’t have much experience in seducing women, though. Kelly could hear the awkwardness in his tone. Looking up at him, though, his vibrating dick still in her hand, she flashed him a gaze that let him know it worked.

“A test huh?” she said with a lurid grin. “Well, in the interest of science, sign me up!”

“Glad to hear you’re so excited about my work,” Marv said as he loosened his tie. “Just to be sure, is there any particular way you’d like to go about it? For this test to work, I want you to feel comfortable.”

“Don’t worry about my comfort, Marv. I’m a professional, remember?”

Her enthusiasm for science growing by the second, Kelly got up from the bed and shed her clothes. She didn’t try to be sexy about it, either. She just took off her clothes in quick succession, starting with her shirt and pants before slipping out of her bra and panties. Marv barely finished unbuttoning his dress shirt by the time she stood fully naked in front of him.

Despite carrying himself as a passionate man of science, he was still a man. He smiled and blushed as he took in her naked features, paying close attention to her breasts and hips. She swore that already-erect dick of his twitched at her presence. She took that as a promising sign.

“You’re uh…very beautiful, Roxy,” Marv said, fumbling a bit with his shirt as he set it aside.

“Thanks,” she told him. “I’m hope that’ll make things easier.”

“It will. It definitely will,” he said, sounding more like a guy not used to being around naked women. “For the record, though, it’s been quite a while since I’ve been with a woman. My sexual experience is fairly limited, so to speak.”

“Then, why don’t you let me handle the parameters here?” she offered. “I know all the basic and advanced-level stuff involving sex. I promise I’ll give that dick of yours a very thorough test.”

Marv cast her a grin with renewed confidence. He still seemed somewhat awkward, especially after she pulled him into an embrace wherein their naked flesh touched. He might not have been the tallest or most masculine figure she’d ever embraced, but he still carried himself with an energy and passion any woman would find attractive. That, on top of the prospect of fucking the first man with a cybernetic dick, got her genuinely aroused.

“Lie down on the bed,” Kelly told him. “I’ll set the mood. Just focus on sharing it with me.”

“Focus…that may be a greater challenge than I thought,” Marv said as he nervously trailed his hands up her womanly curves.

“Then, I’ll help you overcome it.”

Her confident, seductive tone helped settle him down. His trust in her skills secured, he crawled onto the bed and laid down as she’d requested. Kelly followed him, flashing him a few sexy glances along the way. She usually had to maintain a sexy demeanor to keep her client excited, especially the nervous types. From the looks of it, though, that wouldn’t be an issue with Marv. That cybernetic dick of his remained as erect as ever.

Kelly felt it press against her as she got on top of him, hovering over the slim man so that her breasts pressed up against his chest.

“I’m going to kiss you, touch you, and give your dick a quick suck,” she told him. “Normally, I do that to get a guy hard. That might be redundant in this case, but I think it’ll help if we keep the approach basic.”

“Yes. That sounds…logical,” he said.

“Is it scientific, as well?”

“I’m…not sure I can make that assessment.”

Kelly snickered. It was remarkable how a man with a cybernetic penis could still be so anxious while in an overtly sexual situation. She was used to men being intimidated by the prospect of having sex with a woman, but Marv handled it better than most. When she kissed him on the lips, he kissed back in a way that felt sincere. That, alone, made him more decent than most clients.

For a brief moment, they made out, giving Marv a chance to feel up her naked body, even giving her butt a playful squeeze. After tasting each other’s lips – and getting around however many breath mints he’d eaten before her arrival – Kelly channeled her inner Roxy, trailing her lips down his neck and over his chest.

His slim build didn’t have much in terms of muscle, but his skin was still so smooth and warm. What Marv lacked in physical stature, he made up for in good grooming. That counted for something in Kelly’s book. It encouraged her to be extra caring with each gesture, tasting every inch of his skin while gliding her hands down his torso.

“That feels…nice,” said Marv with growing contentment. “You really are a professional, Roxy.”

“I’m just getting warmed up, cyber-stud,” she teased.

He chuckled at her choice of words, but didn’t contest them. If his test really was successful, then that might end up being an apt description.

Sharing his intent to complete that test, Kelly worked her sensual magic, making her way down his torso until she reached that fully-engorged, scientifically-enhanced penis of his. It was still vibrating, the veins throbbing with an energy that wasn’t at all nature, but still very sensual.

“This is uncharted territory in the history of sex,” she found herself saying. “Well, in the name of science and progress, here I go!”

Now feeling like the Neil Armstrong of whores, Kelly carefully caressed the vibrating member with both hands and took it into her mouth. Almost immediate, Marv gasped blissfully at the feeling, his body shifting under the weight of the feeling. If nothing else, that showed that his penis was still as sensitive to touch as any other. However, there were some uncanny distinctions.

“Mmm…this dick,” she said after a few oral teases. “It feels so different.”

“Different how?” Marv asked intently.

“Good different,” Kelly told him. “Very good, in fact!”

She resumed her sucking, squeezing the base a bit more and working her lips along his rigid length with more vigor. As someone who had given oral sex to many men, Kelly knew the intricacies of a penis better than most women. She’d sucked dicks that were too sensitive and others that were not sensitive enough, leaving her with a sore jaw the next day. Every man was different and the extent of their desires rarely matched the robustness of their cock.

With Marv, however, there was no disconnect. Every vein, gland, and contour practically radiated with energy. The fact that it vibrated added even more nuance, as if to remind her that she wasn’t sucking an ordinary dick. If anything, the dicks she’d sucked before had been the beta version, bound by the limitations of anatomy and easily distracted men.

It was like every other cock she’d sucked before had been powered by a crank shaft and Marv’s now powered by a high-performance V8 engine. It was like going from a tricycle to a drag racer. The idea that a penis could be that aroused was enough to make Kelly extra wet, the prospect of feeling it inside her getting more appealing by the second.

As she bobbed her up and down his length, she reached down between her thighs and fondled her pussy in preparation for sex. It usually took a lot more to get her in the mood when her client wasn’t as attractive as the men she fantasized about in the shower. That was why she often kept lube within reaching distance of the bed. She didn’t need any with Marv.

Besides, for such a landmark test, it made sense to keep things natural. In the name of science and great sex, Kelly was willing to take chances too.

“Are you ready for the real test, Marv?” she asked after giving his dick one last thorough lick.

“I’m ready,” he said, breathless yet eager, no longer showing any signs of jitters.

“Then, I’m going to get on top and ride your cock,” Kelly told him.

“And how will I know if it’s working?” Marv asked her.

“Trust me. You’ll know!”

The sexy undertone of her voice told him everything he needed to know. Kelly was just as eager to see what a cybernetic dick could do for a woman. If it could satisfy her, an experienced escort with a promiscuous past, then the prospects were that much greater for all women.

Crawling back on top of him, Kelly straddled the slim man’s pelvis and aligned his still-vibrating cock with the wet entrance of her pussy. Just feeling the vibrating tip over her moist folds was enough to send shivers of delight. She couldn’t remember being so eager to fuck a client before and she’d served star athletes from the basketball team. Her arousal, excitement, and kinky curiosity left her with no reservations as she began the most intimate part of the test.

Holding onto his torso with both hands, Kelly steadily lowered her hips, the extra-hard flesh penetrating her depths with every inch. Almost immediately, she felt a distinct difference between Marv’s dick and every other dick she’d ever had inside her. It wasn’t just that it was vibrating or super-erect, either. The way his manhood filled her depths redefined her understanding of the basics of sex and in the best possible way.

“Whoa!” Kelly exclaimed. “It feels…oh my god, I don’t have words!”

“Mmm…I feel it too,” Marv said, now holding onto her hips.

“Trust me, Marv. What I’m feeling now…it’s a fucking breakthrough!”

She didn’t give Marv a chance to ask for specifics. Being a man of science, he probably would’ve asked for some, even while having sex with a beautiful woman. Kelly wasn’t in any state for questions, though. She was too busy being the first woman in history to fuck a cybernetic dick.

She embraced that role whole-heartedly, moving her body and gyrating her hips in a heated sexual rhythm. She was usually more measured with her clients, starting slow and trying to get a feel for what they liked. For Marv, a man equipped with an unnaturally robust penis, Kelly didn’t hold back. She was focused and determined, as though she were fucking the most important man in the world. Given the promise of the technology he’d developed, that might not be far from the truth.

That technology did plenty to deliver. Between his dick being extra hard and the vibrations within it, he stimulated her depths with every motion. He struck nerves that most women couldn’t reach with even the most overpriced vibrator. It was like every other dick had a limit to how much it could satisfy a woman, but Marv’s cyber-dick shattered those limits and soared above them like a rocket.

“Oh…oohhh my God! Oh my fucking God!” Kelly gasped. “That feels amazing! This dick…so fucking hot!”

“Roxy,” Marv gasped. “These results…so good.”

“Fuck yeah, they’re good! They’re going to…make me…come!”

That shouldn’t have been possible so quickly. Every escort – or even just a woman who received marginal sex education, for that matter – knew that women didn’t orgasm as easily as men. It often took longer, more focused stimulation to get the job done. It rarely just happened by putting a penis into a vagina.

Those rules were out the window with Marv, though. That surgically-enhanced, steadily vibrating dick of his hit all the right spots, along with a few Kelly didn’t know existed. The end result was the quickest, most intense orgasm she’d ever felt.

“Ohhh science!” she exclaimed.

“Roxy!” Marv moaned.

It was like a pleasure bomb going off in her core, an eruption of orgasmic sensations spreading out in every direction. Kelly closed her eyes, threw her head back, and demonstrated more flexibility than she knew she had as she cried out to the heavens in ecstasy.

For a brief moment, every nerve was ablaze with pleasure. Every muscle in her lower body throbbed in conjunction with her release. It was so intense that she dug her nails into Marv’s torso to hold on. She’d probably leave marks that would take some time to heal, but he didn’t seem to mind. He’d already made clear his commitment to testing his research.

“Incredible!” Marv exclaimed. “This test…has exceeded expectations.”

“Trust me,” Kelly said breathlessly, “It exceeded more than that.”

Now beaming with an orgasmic glow, she leaned in and gave the older man an affectionate kiss. A man who gave a woman that kind of pleasure deserved nothing less. Marv, still looking overwhelmed by the results, kissed back. He was actually a great kisser, which helped give more weight to the feeling.

Even as the ecstasy subsided, his member remained fully erect. It was still vibrating inside her as well, providing continued stimulation to her depths. She had to rise up off it, just to give her pussy a rest. However, Kelly wasn’t done yet. There were still a few things left to test.

“I think we can officially say that a cybernetic dick works,” she said after their lips parted.

“Yes, I believe the data speaks for itself,” Marv said in a humored tone.

“You’ve got something that a woman can ride to a good orgasm. That, alone, is a damn good upgrade,” Kelly went on. “Now, let’s flip the script.”

With a seductive grin, she rolled their bodies over on the bed so that she was on her back and Marv was on top of her. He was still catching his breath, but she could see in his eyes as a lingering desire, both to finish the test and have sex with a beautiful woman.

“This time, you set the tone,” she told him. “Fuck me however you want to fuck me. See for yourself what that dick of yours can do.”

“That sounds…logical,” Marv said. “Although, given my limited experience, I may only be able to take it so far.”

“That’s okay. Hell, that can work to your advantage. Most men are more limited by their dicks than their desire. You may be the first man in history who isn’t bound by those limits. Embrace it!”

A look of confidence came over him. In an instant, the unassuming man had the bravado of a six-and-a-half foot tall rock star with an eleven-inch cock. Kelly even found it sexy. It was more than enough to keep her pussy moist and ready for more sex.

“Very well,” he said. “I suppose I’ll finish the test from here.”

“Science never sounded so sexy,” Kelly laughed.

Armed with his new confidence, Marv rose into an upright position so that he was on his knees. Kelly, remaining flat on her back, spread her legs widely so that he had plenty of room to work. He made good use of it, grabbing hold of her thighs just above the knees and guiding his dick back into her pussy.

The entrance was smooth, aided by all the feminine juices she’d released from her climax. Marv’s dick was still vibrating as well, which kept those juices flowing. She let out a purr of contentment upon feeling his flesh inside her again. She saw just as much contentment in Marv’s expression. Now bearing the look of a man immersed in lust and desire, she held onto his shoulders for what promised to be an unprecedented exercise in sexual nuance.

“That’s it, Marv. Fuck me!” Kelly urged him. “Fuck me with that science-enhanced dick!”

Marv responded only with a deep grunt before initiating a sexual rhythm. He kept things basic, utilizing a simple missionary position to get things going. That made sense. If they were going to test the bounds of cybernetic dicks, it made sense to keep things simple.

From there, Marv worked his body, moving his hips in a steady procession of sexual motions. With every act, his vibrating manhood slithered inside her vagina, probing and stimulating her depths. A fresh round of sensations coursed through her body, evoking moans and purrs of delight. Now clinging to his shoulders, Kelly sought to embrace a new era of ecstasy with him.

“Oohhh Roxy!” he said. “That feels…amazing. I’m going to…achieve climax…soon.”

“Already?” Kelly teased.

“Don’t worry. I’m not stopping…the test!”

He didn’t give her a chance to make a joke about premature ejaculation. Kelly reminded herself that she was fucking a man with a cybernetic dick. For all she knew, that was the first flaw Marv fixed when he made his prototype.

He stepped up the pace for a brief moment. Then, he slowed his movements, his expression shifted, and his body shuddered under the weight of his release. Kelly made sure he enjoyed it as much as she enjoyed hers, spreading her legs extra wide – more so than she did with her other clients. She could feel it as that big, throbbing cock of his tensed inside her depths in accord with his release. Marv wasn’t quite as vocal as she’d been, but the results were just as clear.

“Wow!” he gasped. “That is…unprecedented.”

“Not the word I would use,” Kelly laughed, “but still plenty sexy!”

Marv laughed as well, lingering for a moment in the ecstasy, but soon resumed their sex. There was no refractory period. His dick didn’t go limp, even by a little. He just kept on going as though it were nothing.

It was a strange phenomenon for an experienced escort. While Kelly had been with a few men who could go multiple rounds in a brief span of time, they had to work extra hard to rise to the occasion, so to speak. With Marv, there was no need. His dick remained at full-throttle, limited only by his desire to use it.

“This…is going to test my stamina,” Kelly said to herself.

From there, she held on as Marv kept fucking her with superhuman fortitude. He kept the rhythm steady and movements thorough, making an effort to work his flesh within hers. He didn’t just pound away, as so many men often did, but Kelly wouldn’t have blamed him if he did.

Making good use of her efforts and the sturdy hotel bed, she and Marv went at it. Their naked bodies moved and grinded together in a mesh of lust and intent. His dick kept vibrating, her pussy kept throbbing, and the pleasure kept flowing, unburdened by prohibitive anatomy. It led to her having another orgasm – once again, in rapid time. She felt him climax as well shortly after. It wasn’t just a single plunge into a pool of ecstasy. It was like taking multiple dips.

“More data…more results,” Marv moaned after yet another orgasm.

“Yes, Marv! More…give me more!” Kelly exclaimed.

Her encouragement kept him going. They shifted around on the bed, having sex in various positions. They couldn’t get too elaborate, though. She could tell Marv was not used to so much physical exertion. Even with an enhanced dick, the man was no athlete. She shuddered to think how much he could fuck if he went to the gym regularly, albeit in the best possible way.

Before long, Kelly lost track of how long they went at it or how many orgasms she’d had. It was definitely over the allotted time he paid her for, but she didn’t care. She didn’t even plan to bring it up. The man had done more than enough to justify the overtime. In fact, as she felt the rush of yet another orgasm, Kelly found herself coming to some realizations that were only possible under the weight of good sex.

“This feeling…need to know more,” she said.

Marv didn’t hear that. At that point, he was so winded that his face dripped with sweat. Eventually, after another release, he collapsed on top of her in a heap of exhaustion. She ended up having to catch him so that he didn’t slump over awkwardly. It was probably a good thing too because her pussy had reached its limits too. She was definitely going to be sore tomorrow, but for all the right reasons.

When the sexual movements finally ceased, Kelly helped him settle. She laid him down on his side where he could catch his breath. She laid next to him, needing some time as well. At one point, he pushed a button on his watch again, which he hadn’t taken off. Just as before, his dick reacted, quickly becoming flaccid.

For a while, they just lingered in silence, taking time to process the moment. Usually, the post-coital silence was the most awkward part of being an escort. Tonight was different, though. In fact, it was quite revealing.

“I’ll say it one more time…wow!” Kelly said. “Marvin Herbert, you’ve made one hell of a breakthrough.”

“So it would seem,” he said, still panting heavily. “The test…was successful. This bodes very well for my research.”

“You have no idea,” she replied, “and I’m not just saying that on behalf of all women who love great sex.”

“What do you mean?”

Kelly then curled up closer, the heat of their naked bodies mixing once more. She smiled at him and he smiled back, still bearing the demeanor of a man who wasn’t used to being with a naked woman.

He still had the look of a man who understood that they’d just achieved something special. In fact, tonight might very well mark a change in history of sex, as well as a profound change in Kelly’s plans.

“An hour ago, I was just an escort trying to pay my tuition. I had no major, no goal, and no career path, whatsoever,” she told him. “That all changed, thanks to you.”

“I’m honored,” Marv said, “but I’m not sure I understand the implications.”

“You will. I promise, you will,” she said with great confidence, “because tomorrow morning, I’m heading down to the Centerfield Science Office and changing my major. I’m going to dedicate the rest of my life to science and all the ways it can make sex great.”

“That sounds rather ambitious.”

“Not as much as you think,” Kelly quipped. “The way I see it…if this is what science can do for a penis, I can’t wait to see what it can do for vaginas!”