With that he removed the probe but left the flanges of the proctoscope as their maximum width as he selected a good size dildo from the instrument table. Jennifer, without any instruction, had begun to refill the giant syringe. As the doctor lubricated the dildo, Steve released the proctoscope and slid it out of my rectum. Almost immediately, Jennifer had the syringe stuck in me up the hilt. I could feel the cool lubricant fill me up again for quite some distance. And then, as soon as she withdrew it, the doctor pushed the head of the dildo against my sphincter muscles. Since they had already been loosened up, it slid in without too much effort. At that point I again experienced that feeling of intense fullness and could feel the pressure of the dildo against my prostate as well as the walls of my rectum. More precum began to make its way to the collection area of the tubing.

The doctor began moving the dildo in and out with a regular, slowly accelerating rhythm. As he did I felt as it there were pulses of erotic energy surging from my prostate to my penis and I could see a thin bead of pre-cum almost filling the tube all the way up to the collection area, which was itself getting fairly full. Given the amount of lubricant forced inside and the increasing vigor of his movements it wasn’t surprising that little bursts of lube spurted out as he quickly withdrew the dildo almost all the way before thrusting it forward again. “It’s time to assess how Jim responds both with and without additional stimulation,” the doctor said and as he did, Blake turned some dials on the electrical box that the various wires went to. First I felt spasms in the thigh muscles. They began to twitch and tighten in a rhythmic pattern as first one than another of the patches received a bracing current from the box. Next I felt my buttocks quiver as the muscles clenched tight and quickly relaxed. Finally, a tingling sensation surged through my distended nipples. It reminded me of how engorged they, and my penis, had become thanks to the suction they were experiencing. My mind felt boggled; I couldn’t decide what to focus on; there were so many powerful feelings assaulting my body all at the same time.

The doctor continued his assault on my ass for some time and after a while the lube stopped squirting out with each stroke but their depth and intensity remained powerful. The electrical current followed a rhythm of its own, pulsing faster and slower, stronger and weaker, leaving my thighs and buttocks a mass of pulsating muscles that I no longer could control at all and my nipples little epicenters of intense sensation that bordered on pain.

Finally, and right around the time when I didn’t think I could take much more without a cosmic ejaculation, the doctor stopped and popped the dildo out of my ass. The electrical stimulation also subsided. “It’s time for phase III,” he said. “Beverly, I see we have collected quite a bit of pre-ejaculate already. I think we should clear the tube before we continue.

”Beverly then disengaged the suction on the small tube that attached to the tip of my penis, but not the suction that continued to hold me in a super erect condition. I watched as she slipped the “U” shaped collection trap off the continuation of the tube to the suction machine. I hadn’t realized that it was detachable but she now held the U in her fingers and lifted it up high so that all the other students could see it too. With the doctor’s encouragement she brought it down and toward my lips. Jennifer had come to the other side of my head and was stroking my cheek on her side, letting her finger run across my lips as well in a slow, teasing fashion. Smiling at the doctor, Beverly tilted the U into my mouth so that the end of the tube was now like the tip of a straw.

“Suck,” she said to me, in a firm, demanding voice. I complied and felt the warm, slightly salty fluid drain into my mouth. Jennifer whispered into my ear, “Don’t swallow right away; let it roll around in your mouth. Savor it and imagine it’s the juice of the most beautiful pussy you’ve ever seen.

” I could feel my cock pulse as she said that and I obeyed. “Go ahead, bottoms up; swallow that now and we will continue.

” I did. It tasted good as it slid down my throat.

“For phase III, we need to assess Jim’s penile functions. His anal functions appear to be excellent and his muscle responses to stimulation are vigorous and normal. I think we have cured his bowel movement problem by removing the accumulated content of his colon but we can be sure on the next visit. Let’s prepare the patient for phase III.

”With this Steve and Beverly slowly disconnected the pump from its power source and then lifted the cylinder off my cock and balls. Jennifer took my cock in one hand and Blake took my scrotum in his hand so that they could gently massage and stroke them as they came free. It was a relief to have a mere erection rather than the highly taut, stretched out genitals that I had possessed up until this point in the experiment. Blake used his other hand to massage the skin where the cylinder base had dug into it; it felt good and soothing.

Meanwhile the doctor had been busy at the cart, gathering up another device that he handed to Blake. It looked like some sort of miniature scaffolding and I quickly realized it has a similar function as Blake set it around my cock. A couple of bands allowed him to secure my erect cock to the metal scaffold that would keep it erect, at a ninety degree angle. The scaffolding extended above my cock, as the cylinder had, and at its top there seemed to be a pair of slots one above the other. As soon as he completed that work he worked a snug band around my testicles so that they felt isolated and distended. As this was going on, Steve had released the suction on my nipples so that they relaxed once again. He lifted the cups and massaged the skin for a few moments and that, too, felt wonderful.

“All right, let’s get started. Ignoring the slots at the top of the scafflold, the doctor who was now holding a long, lubricated rubber like tube in his gloved hands nodded to Jennifer who swabbed the tip of my penis with an iodine colored solution. After that he quickly began to thread the tube, a catheter, into my opening. I felt a burning sensation as it began its passage but that feeling seemed limited to the tip of my penis. The passage of the catheter further down actually felt good, especially when it slid past my prostate. If the suction were still on I am sure there would have been more pre-cum. I felt the catheter stop. “We’re at the bladder. Now, Jim, bear down as if you are going to pee.

” As I did I felt the catheter slide into my bladder and the urge to pee seemed uncontrollable; it felt exactly like I was peeing but nothing seemed to come out. When I looked down I saw that the other end of the catheter had three outlets and that middle one was clamped shut. Before I could figure out what might happen next, Beverly took a 30cc syringe, attached it to one of the outlets and slowly pushed the contents into the catheter. As she did so I felt the doctor give a little pull on the entire catheter but it seemed stuck; it wouldn’t come out and I felt a pressure somewhere in my groin. “The balloon is full, and the catheter won’t be going anywhere until we’re ready to let it,” he said. “It’s time to get Jim ready for his big moment.

” With that he took the tube that ran down from an IV bag that hung from a post Blake has moved over without my noticing it until now and held it in his hand. “First, we are going to drain Jim’s bladder and then fill it with exactly one liter of saline solution.

” He slid a plastic bag of some kind onto the clamped outlet and released the clamp. A giant gush of urine flooded down the tube. I realized I hadn’t pissed in some time and that the tension of the experiment had produced quite a bit of urine. Eventually the flow stopped even though I felt like I was still pissing, and the doctor attached the IV tube to the third outlet. The second outlet, draining my bladder, was clamped off. I could feel the cool solution pulse its way up into my bladder, slowly engorging it until I felt as if I absolutely must pee again but I couldn’t.

“We’ll let Jim stew in his own juices, as it were, while we finishing the filling.

” With that he abandoned the catheter, which didn’t budge of course, and took a new device in his hand, a large black nozzle that was attached to a very large red enema bag on another IV stand.

Jennifer did her thing with the lube and the giant syringe, and the doctor slid the big nozzle in my butt and let the liquid flow. It felt warm as he explained that it was an isotonic saline solution and would leave me quite full when the entire 4 quarts had been poured into me.

When the bag looked completely empty and my stomach a looming bulge, he slowly pulled the nozzle out, warning me not to loose a drop. The final step for my ass was the insertion of yet another plug. This one was also quite large, shaped something like a torpedo and made of silvery metal and a dark rubbery compound. I noted that wires ran from it and were soon attached to the electrical box. That done, the doctor returned to the catheter, unclamped it, and immediately inserted a more slender silvery catheter inside the central channel. It threaded its way up to the end of the catheter so that the end of it was inside my bladder. A wire ran from it too back to the box. Steve, meanwhile, reapplied the cups to my nipples and I could the vacuum pull them tightly against the metal points. Jennifer checked that the electrodes on my thighs and buttocks were firmly in place, and Beverly applied two more sets of pads to my groin, one pair just above my penis, where my pubic hair had been and another set a little higher and more lateral than the first set. They all stood back to admire their work.

“This is stage one of phase III,” the doctor said as he activated the current. My entire body felt as if it were going to leave the table. A current throbbed from my rectum and colon all around my groin while other currents ran down my cock and into the entirety of my bladder, across my nipples, through my groin muscles that twitched and tightened to the rhythm chosen by the doctor. My thigh muscles were also pulsing, twitching and jerking to the same tune. My buttocks clamped down as they never had before. Time evaporated. I felt as if I had become weightless in the thick of a timeless ether, floating through clouds of ecstatic bliss. And then it stopped, partly. “And now for stage two,” he said as he withdrew the electrified catheter and allowed the saline to drain from my bladder. As soon as it had I realized he had been at the cart again and now held a metal instrument in his hand. It had a long very thin and flexible shaft and a large metal bulb at the end that looked something like an over sized suppository. He lubricated it.

The sound, which is what he called it, was threaded through the slots at the top of the scaffold so that the bulb now stood a breath away from the tip of the penis and the shaft ran straight up through the slots to the doctor’s hand. He lowered it. I could feel my urethra stretch like it had never stretched before. The scaffolding held my penis in perfect alignment and the slots kept the sound aimed straight and true into the depths of my urethra. The doctor paused and told me to take a deep breath and slowly exhale. As I let the air out he let the bulb slide deeper inside me.

I could tell that Jennifer, who was between my legs next to Dr. Gray, was watching it descend and I imagined she could see it make the skin on the dorsal side of my cock expand as it moved downward.

The doctor went deeper and deeper, sometimes rotating the head inside my urethra, sometimes withdrawing it a bit before going further. But he went further and further, relentlessly. It had an eerie, delicious feeling, and I could really feel it as it passed my prostate and headed straight for my bladder. Suddenly, then was a popping feeling and I knew it was inside. The doctor then withdrew it and the urge to pee returned but I had nothing to release. He then nodded to Blake who turned a dial and the electrical currents on my thighs, groin, nipples and through most of my colon returned. The doctor began a rhythmic in and out motion, with a little rotation thrown in as the sound moved methodically down through the slots and along the length of my urethra. As it stimulated my prostate to new heights Beverly applied a vibrator to the shaft of my penis and Jennifer put her hands on my cheeks, letting her finger slide inside my mouth. My body was writing with a will of its own and I could feel my entire consciousness center more and more on the stimulation that was bringing me to the inexorable climax. As my entire body began to tighten and I sucked hard on Jennifer’s fingers, the doctor slide the sound out of my cock, Steve released the straps and pulled away the scaffolding, and Beverly grasped my cock firmly and applied the vibrator to the head, rotating it around and around as her hand milked my shaft. The jerks and twitches intensified, my nipples felt on fire, my bowels in convulsions, as a sudden burst of cum shot out of my cock and at least five feet into the air. More bursts followed and I could hear cheers and applause from the other medical students.

I know that the doctor and his assistants must have removed the remaining electrodes and drained my bowels of the enema solution but I have scant memory of it. I do remember awakening some time later, lying beneath a warm blanket on a cot in a small but comfortable room. Had it been a dream? I don’t think so but it has been an experience clearly and surely unlike any I had ever experienced before. Sure enough, my bowel problems was solved and I had a blissful week before returning for another demonstration.

Two weeks later, Dr. Gray stood at the foot of the table as the same group of attractive young med students filled the three risers around the table. I recognized many faces but didn’t see Steve and Beverly among them.

Dr. Gray introduced the new session: “Today, we will give Jim some follow up exams but on a comparative basis. You will be treating hundreds of patients every month and it important to understand the variations in human genital-urinary response. This session will make that point clear.

”As he was speaking, Blake and Jennifer, who I recognized from the last session, wheeled in two more tables on which Steve and Beverly were carefully positioned. Each of us was in the same predicament: our butts at the end of the table, our legs raised and secured in stirrups, the superior half to the table tilted up so that we could see what was happening. We all nodded at each other. Beverly was even more striking than I had imagined she would be.

Her moderate sized breasts had a gravity defying density and jutted out from her chest at a sharp angle, capped by perky nipples that were at least a half inch long and clearly excited. Steve had a good physical build like mine, with nicely defined pecs and strong shoulders. Like Beverly and me he had been rendered hairless from his navel to his feet and between his legs hung a thick circumcised penis that was still at rest but at least five inches long. His scrotum was also rotund and full; it draped down from his groin as if it were bearing a ponderous load.

Dr. Gray explained the goal: “We will make sure the models are all thoroughly cleaned out and then conduct a series of tests of their sexual responsiveness to various stimuli. Since they are all 35-36 years old and in good physical condition, the tests will be a useful indication of the variation among similar patients; later, we can examine responses among a wider variety of patients.

”Blake and Jennifer and several other students set to work. This time it seemed as if most of the class had a role in our preparation. Surprisingly, we were all helped to our feet almost immediately. Nude, we stood in the center of the cluster of eager students. I felt better knowing I wasn’t alone but I also felt almost overwhelmed by the number of hands and eyes that were busily at work. I was surprised to see three students with gloves extract large gobs of a white cream from spray containers and begin applying the material to each of our bodies, from Beverly’s pubes to her anus, and for Steve and me, from our chests to our ankles. Soon, we were all covered with the cream and told to stand still. Our legs had been splayed well apart and kept that way with spreader bars. The cream came up to our perineal area and down the inside of our thighs along with everywhere else. After about 7-8 minutes we were told to stand against the far wall where I realized there were ceramic tiles on the wall and drain holes in the floor. We had to raise our hands and three students quickly rubbed the creamed areas with cloths: it was soon obvious that all our hair was coming off. As they finished I heard a stream of water start to run and we were told to raise our arms. Soon, a soft, steady stream of water ran over our bodies. Any remaining cream or hair was soon flushed down the drain.

Although I was by now used to being naked in front of a group of curious and somewhat perverse medical students, I felt an extra tinge of embarrassment: my skin stood undraped, free of its covering of fine but well-distributed hair. The hair seemed a part of my masculinity and maturity; I felt as if I was reverting to an earlier form of myself, more vulnerable and innocent but the thought carried a strong erotic charge that was anything but innocent. I noticed that Steve and Beverly’s faces had a slight blush to them and felt quite sure mine did as well.

We were toweled off (the students seems to linger on the pelvic area and my penis was clearly responding approvingly, as was Steve’s, and from her moans, I could tell Beverly was in a similar state). We were taken back to the tables we had been on. A female student wrapped a cock ring around my now hairless scrotum and penis and then did the same to Steve. Beverly had bands run around her breasts, making them protrude even more defiantly. Her nipples and our penises were definitely rising to the occasion. In fact, I could see a droplet of pre-cum take shape at the urethral meatus of Steve’s penis. Dr. Gray also noticed and commented, “We need to attach the collectors as soon as the men are back on the tables.

” Quickly, all three of us were secured to the tables, our legs in stirrups and straps and our buttocks right at the edge of the table. I could see two students advance with a clear plastic device. It had a bulge at one end and this end was fitted around the head of Steve and my penises. This led to a tube that had a globe-like trap in it while the far end entered a housing on a small motor. The motor was switched on and I could see Steve’s pre-cum enter the tube and collect in the clear, spherical trap. I could feel the firm and pleasurable pull on my own penis head as well; if my penis hadn’t been fully erect before, it was now.

Beverly received her own, similar device: a smaller cup attached to a tube that also generated a suction; as one student used a clitoral re tractor to withdraw the hood, the devices was slipped snugly around her clitoris; she gasped as the suction drew her clit upward, doubling its size instantly. We were now all in what promised to be an extended state of arousal.

Dr. Gray announced it was time for the first test: the anal retention of a laxative solution. Our three tables, instead of being side by side were arranged at 120 degree angles to each other so that our pubic areas pointed toward the same central area.

We could each see what was being done to the other two of us. A set of large clear enema bags were wheeled into the central area as we were each fitted with a double balloon retention nozzle. I watched as a student lavished a gel on my nozzle, glancing from it to my erect penis, pre-cum extractor and eyes in rapid succession. She then began to slide it into my anus. As the sides of the first balloon made their way forward I could that familiar stretching feeling increase and build until it reached a peak and then rapidly subsided as the balloon penetrated past my sphincter. A wave of relief swept over me, just as it did when a butt plug finally reached its resting place inside me. I knew Steve and Beverly had similar experiences because I could hear little gasps come from both of them almost at the same time. Then there was the incredible sensation of a mounting pressure building just inside my anus as the first balloon was pumped to its full size. I could feel the pressure pushing in every direction but out. There was no way the balloon could be retrieved in its expanded state or any fluid slip past it. The outer balloon was soon fully expanded too and tightly pressed against my anal opening. I was ready.

The nozzle hosing was quickly attached to the tubes dangling from the bags. Dr. Gray explained that each bag contained 4 quarts of warm water into which eight, pulverized, 5mg biscodyl tablets had been thoroughly dissolved. The normal dosage was one tablet orally. He assured the class that this mixture would generate a powerful urge to evacuate almost immediately, something the balloons would definitely prevent. Steve, Beverly and I glanced at each other, looks of apprehension mixed with a definite excitement. The clamps released, liquid poured into my rectum at a rapid rate. I felt the rest of my rectum and then colon expand to what felt like the size of the inner balloon. It was a powerfully erotic sensation and I noticed an increase in pre-cum as well as much more rapid breathing coming from Beverley. Two of the female students were helping her manage by massaging her breasts and abdomen respectively. Two male students did the same for Steve and me, massaging our abdomen and our tightly bound testicles with gentle, arousing strokes.

Within a minute, while half the solution was still in the suspended bag, I felt the first wave of peristalsis. My bowels tried to expel the fluid but it had nowhere to go. I could feel the wave make its way to the rectum only to butt up against the immovable balloon. It then subsided. From the squirming, I could tell that my two fellow subjects were having the same experience. With the liquid entirely inside me, the waves increased in intensity. My bloated abdomen writhed, desperately trying to let the laxative have its way but it was to no avail. Each wave felt stronger than the last. Each wave went on for 20-30 seconds and was no doubt somewhat like labor pains, but with a blocked canal. A student prodded another one, and pointed to where the outer balloon was lodged against me: noticing this I realized that I could feel a tiny trickle of a few drops of fluid slipping down my buttock on their way to the floor. Not enough to be any relief at all. Dr. Gray glanced at a student next to Steve who said, “Six minutes, seventeen seconds.”

I looked to my left and realized that I too had a student timing my submission. Who would beg for relief first?I felt a bit delirious. The sensations were incredibly intense and I felt as if I were attempting to evacuate the biggest load I had ever had and yet, and yet, each effort only led to another even more desperate effort. I drifted into subspace, aware of what surrounded me in a dimmer way, focused on the remarkable mixture of bliss and distress that engulfed my bowels and my being. Minutes and minutes passed, the waves relentless in their determination to force the liquid past the balloon. Finally, I heard a cry, “I can’t stand it anymore, please, let me expel this stuff!” come from Steve. He’d thrown in the towel and Beverly quickly followed: “Me, too; I have to let it out; it’s going to spew up into my mouth if I don’t!” I didn’t feel any sense of victory: I wasn’t really competing with them, and I realized that the bliss that came with the pain had overcome me and that by drifting off I had escaped from the most intense feelings of distress. I felt another few super intense waves pass through me as I watched student deflate their balloons. As soon as they did, liquid began to surge out of Steve and Beverly, straight into the collecting buckets that were held against their bottoms. Soon I too was emptying my bowels of the by now thoroughly churned mix of feces and fluid that had overwhelmed me.

As a kind of pause in the experimentation, we were each given a colonic rinse that felt extremely soothing. It flushed out any remaining laxative and allowed us some time to recompose ourselves. I became aware again of our continuing state of arousal and could see that Steve and my collecting traps were half full of pre-cum already.

A good-looking male student was making sure Steve’s erection remained perpendicular to his body while a fully figured female student did the same for me. Beverly enjoyed the soothing touch of a male student massaging her breasts and a female student sliding a finger up and down her labia in slow, idle strokes.

Dr. Gray then resumed the testing by instructing some of the students to bring out the coital stroke manifester. The CSM was a device with a central core and three piston-like rods extending from it at 120 degree angles so that one pointed directly at each of us. At the end of each rod was a sizable dildo, probably 8 inches long and at least 5 inches in circumference, with a very realistically shaped glans at the end and an opening to simulate the urethral meatus. As the device was being readied, we were each approached by students who massaged our rectal tissues with a soothing cream and then inserted the nozzle of a large bulbed syringe. I could feel a cool gel fill my rectum to the brim and knew my two partners were having the same sensations. Our anal test was not yet over!Once ready the piston rods were slowly extended until they were poised right at the entrance to our rectums. I could feel its firm pressure against me and knew that soon it would bore its way inside. After a nod from the doctor, a switch was thrown and the dildos began their penetration, very slowly at first. I once again felt the sense of stretching and mild pain as it relentless forced my sphincter muscle to yield to its pressure. A steady increase in sensation followed by that familiar “pop” like feeling as it slid into my rectum. Passing the point of greatest diameter filled me with a sudden sense of deep pleasure—and with a very formidable dildo!

Again, I heard gasps as Steve and Beverly experienced that same sensation. The dildos rested in place. The still before the storm. Dr. Gray explained the test: “We will activate the stroking mechanism. Each subject will receive the same rate and depth of penetration. In addition, at the half way point to the maximum settings, we will activate the electrical stimulation that the suction devices are equipped to provide. We will be timing for elapsed time to orgasm for each subject.

”The machine began to set up its rhythm. I could feel it pushing well up into my rectum until it was pressing against the wall where it curved into the descending colon. In doing so, of course, it passed my prostate gland, producing a noticeable surge of sensation and pre-cum at the same time. I had no control over the rhythm as it built to a faster pace but I could see that Steve and Beverly were writhing in their straps and that Steve’s thigh muscles were twitching from strong contractions as he tried to adjust his buttocks to maximize the pleasure and minimize the pain. Students pinched each of our nipples as we slid further into an altered state, focusing almost exclusively on the powerful sensations of the mighty dildos assaulting our rectal canals. I noticed that students had attached a large clear suction device to Beverly’s vagina so that any fluids produced could be collected, just as our pre-cum had been.

The sensations grew more and more intense when I felt a sudden tingling sensation at the tip of my penis. My awareness rapidly shifted to my glans as I realized a pulsing electrical current had begun to run through the rim of the collecting apparatus that fit around the coronal ridge. It made my penis stiffen to an unheard of degree. I gasped as my attention fluctuated between my penis and my ass. I could hear short shrieks coming from Beverly who was receiving similar shocks to her clitoris and sharp gasps from Steve whose penis looked like it was a ten inch skyscraper, rigid as steel and standing straight up. This was incredible. More than I could bear, in fact. With a desperate arch of my back and stiffening of my legs, as much as the straps and stirrups allowed, I shouted an unintelligible, “Agh!” and released my load. Just as I was about to ejaculate, a student slid the collecting tube off my penis and attached a hand controlled suction device: my semen shot into it and I could see it splash against the sides and collect, a pool of milky white goo. Simultaneously a strong stream of very warm fluid shot out of the tip of the dildo deep inside my rectum. It had a startling but also incredibly sexual effect, as if I had just received the ejaculate of a stallion. I just managed to hear a “12 minutes, 33 seconds” before hearing similar exclamations of “13 minutes, 14 seconds” and “13 minutes, 48 seconds” for Steve and Beverly respectively. Students inserted pipettes into the collecting cups, siphoned a small amount of semen for testing, and then, surprisingly, brought the cup to my lips. Tilting it I was able to drink it down in three gulps. Another student brought over the trap full of pre-cum and said, “Have a chaser,” as he let me drink down all of the pre-cum I had produced. Another student disconnected the suction device from Beverly’s vagina and held the collected fluid to her lips as well. We each savored our own juices and slowly drifted back toward a normal state of consciousness.

Dr. Gray proclaimed the tests a success. “You can see the various ways in which similar individuals give different responses, in duration, in forms of facial expression, in muscular tensing, and orgasmic achievement. This will be valuable knowledge for you as you begin your own practice.” Two dozen more doctors, each with their own practice: I contemplated the thought. My days as a model and test subject felt like they might be just beginning.