I lay the measuring tape along the length of Taylor's magnificently rigid cock and squinted. "All right, that's...10.1 inches today, up from 9.83 last time we checked. My goodness, that's significant growth for just two days." I glanced up at his face; as I expected, he was blushing furiously. Silly boy. Clamping down on my own emotions, I wrapped the tape around his member: 6.2 inches around. Holy cow, he was damn near two inches thick...and only getting bigger. I wrote the results down dutifully:

Day 40. Length: 10.1 inches. Girth: 6.2 inches. Growth since June 3: 0.27 inches.

As I noted the results, I felt my womanly juices start flowing. I couldn't help it, and I know he could tell it was happening, because his splendid manhood stiffened even further—if that was possible—and almost seemed to quiver.

He had to be sensing my pheromones, because the smell wasn't obvious yet...Yes, there was definitely something unusual about my son. Whether it was something bad, however, remained to be seen. Certainly, it required careful study, and much more...experimentation.

I sat back on my haunches; he glanced down as my bare tits bobbed, and his handsome face flushed again. He clenched his teeth, and I knew he was hurting.

I lifted my hands and pressed my breasts together; a bit lasciviously, I have to admit. I had come to enjoy these training sessions at least as much as my son did, and I'm afraid I was already salivating; either way, I'd be ready. "So what will it be today, Tay-bear? My tits or my mouth?"

Face red, eyes glued to my hardening nipples, Taylor stammered, "Um, uh...both?"

I lifted an eyebrow. "Do you think you could handle both?"

He let out a long breath. "Yeah. Yeah, I really do. I, you know, I go back in my room and I, um, I jack off for like an hour afterward every time we do this."

My other brow shot up. "And you come to orgasm?"

"Oh yeah, several times."

My scientific curiosity was tweaked. "And does the volume of semen remain the same each time?"

"The decrease is slight, but noticeable," he said, a bit more confidently. If there's anything Taylor has inherited from me rather than his beautiful sperm-donor father, it's his scientific attitude.

"I'm beginning to formulate a hypothesis about you," I said thoughtfully, "but it needs more study first. Are you ready?"

"Yes, ma'am," he said fervently.

"Very good. What first?"

"Mom...I want to fuck your tits!" he said daringly.

"My, such language," I cooed, pressing my large breasts together and brushing my fingers over my nipples. "These tits?"

"Hell yes!"

"And what do you want me to do while you're sliding your big cock between your horny mommy's tits?"

"I want you to suck the end of my cock and pinch your nipples, Mommy! I want us to both come!"

My adult son's use of the term "Mommy" just about made my cunt melt...I don't know why, but it always did. The thing was, I didn't know how much longer I'd be able to hold onto the final shreds of that damned incest taboo. I ached to attack him just so I could get his huge hardness inside me, pumping away...but I digress.

I eased forward on my knees and wrapped my tits around the warm hardness of my eighteen year old child's ten-inch cock, and as he began to thrust, and I began to take his glans in my mouth on the upstrokes, and I rubbed my nipples and we both began to moan our enjoyment, my thoughts drifted back to how this had all begun, just 40 days before...

**** My son's expression was grave as he sat down across from me at the kitchen table. Without preamble, he said quietly, "Mom, I think there's something seriously wrong with me, from a developmental perspective. It's a male issue, and I normally wouldn't talk to you about it, being that you're my mother. But you're also a urologist."

I looked at him steadily. "I can recommend a male colleague, if you like."

"I don't think so. You're the most popular urologist in the city, and I know there's a reason for that. You're the best."

I really am good, though I'm popular because most males would rather have their penises handled by an attractive woman by than another male. But I didn't tell him that. "What's the problem, son?"

"Well...there's no discomfort or any evidence of deformity, but...my penis seems to be growing unusually fast."

I laughed lightly. "Oh, don't worry, that's common for a young man your age. I know you hit puberty quite a while back, but you can still get occasion growth-spurts, so to speak."

He blushed and sputtered, "But Mom, three more inches?"

I lifted an eyebrow; apparently, my little boy had already reached his mature size. If he still had some growing to do, the girls were certainly going to be very happy with him in a few years. "Admittedly, that's quite a bit, but hardly unheard of as a young man matures..."

"In three weeks?"

My eyes widened. "Taylor! Are you joking with your poor mother?"

He was so red by now that I thought he might burst into flame. "Of course not! Would I tell you something like this if it weren't true?"

I had to admit that he wouldn't. Taylor's a shy boy, and I'd never even had him mention anything like this to me before. "So tell me what happened."

"Well," he said, his color receding somewhat, "you know how guys are always measuring their erections, right?"

"Of course."

"Well, three weeks ago, I was...stunted for my age. I hate to admit it, but I had a pretty small erection. I mean, it was just over three inches long. And that was if I was liberal in reading the measurement, okay? Then, all of a sudden...well, I started feeling weird all the time, especially...well, when I was looking at girls. Then suddenly my jockstrap in PE didn't fit anymore and I had to get a bigger one. The coach thought it was funny. Then last week, I had to get a bigger one. And, um, that's why I asked you to buy me new underpants the other day. The old ones were, uh, too tight. I guess my testicles are getting bigger, too."

"I see."

He presseded on. "Well, I knew I was getting bigger, OK? Then yesterday when I measured, it was...well, just over six inches." He looked at me with unshed tears in his eyes. "Is something wrong with me, Mom?"

Oh, the expression on his face just made my heart ache. I reached out and took his hand and said fiercely, "Honey, that kind of growth definitely isn't normal for most boys your age, but I don't know if it's wrong for you. Let me do a few tests, and we'll keep an eye on it, okay?"

"Okay," he said trustingly.

****

The blood tests I got back later showed that everything was normal, and he displayed the same hormone levels, more or less, as any young man would. It was time to go to the root of the problem, so to speak.

Taylor had trouble presenting himself to me, just as any teen would, especially given our relationship. But I put on my no-nonsense attitude to make him stand in front of the couch and strip. I was able to maintain the appearance of a professional attitude...but I've always felt a little frisson of anticipation when I'd had a young boy strip for me in my office, and somehow, it was heightened just knowing that it was my son. As he peeled out of his shorts and T-shirt, revealing tight muscles and sun-browned skin, I found myself pressing my legs hard together and squirming, to tease sensations out of my clitoris...though of course when I realized what I was doing, I stopped immediately.

Sometimes when a man or boy presents himself to me, he's erect already. This was not the case for Taylor, who looked away shamefully, face bright red. His penis was as flaccid as any I'd ever seen, but it was noticeably mature, and his testicles hung large and low. I squeezed my legs together again, and to my shame felt my nipples inflate.

I cleaned my throat. "I can't measure your erection until you have one," I said gently.

"I'm not sure I can get one while you're looking at me," he mumbled.

"Just...think sexual thoughts. Stroke it if you have to. Don't be embarrassed."

He looked at my face, then his eyes trailed down to my erect nipples...and his cock leapt skyward. Within ten seconds it was pointing straight up toward his chin, thick and well-shaped, with a slight bend in the middle.

I took my measurements quickly, with a flexible tape I had on hand, and wrote down:

Day 1. Length: 6.3 inches. Girth, 3.74 inches. Growth since approximately April 6: est. 3 inches.

"That's good," I said, patting his erection absently. "You can put it away n—"

I didn't expect him to come all over me. But that's what he did, before I was even finished speaking. And holy shit—he must have been saving it up for a while. You could have filled a soda bottle with his ejaculate.

The poor kid fainted dead away, possibly from sheer mortification, and fell back onto the couch.

"Ooookayy," I said, and checked to see that he was uninjured. He was fine, so I arranged him on the couch and went to my room to take a shower, change clothes—and fuck myself with my battery-operated boyfriend for an hour.

Day 3. I practically had to drag Taylor into the living room for his measurements this time. "Forget it," he said flatly. "There's no way I'm going through that again. I mean, come on, Mom! If I lose control again, I'm gonna die of embarrassment."

"Nonsense," I said firmly. "You'd be surprised how often that happens to me, and not just with young boys. Males will be males, and I can't blame them for it. It's just natural. And we do have to do this, to make sure you're healthy. How can I know what going on if I can't get a few baseline measurements? Now: do I have to undress you myself, or are you old enough to take care of it?"

He just turned his back and took off his clothes. I watched the play of his tight muscles as he did so, and studied his hard buttocks with interest. When he turned around, blushing furiously (I couldn't believe a son mine could possibly be so shy), he was again as flaccid as they come. If his penis could have retracted back into its body, I believe it would have.

I rolled my eyes. "How am I supposed to do my job here if your body won't cooperate, Taylor?"

"I dunno, Mom. But it just won't. I'm too embarrassed."

Well, I figured I knew how to fix that. Sighing, I tugged my blouse up over my head.

"Mom, what are you doing?!?!" he demanded, wide eyed.

As I unhooked my bra and let my breasts swing free, I said, "I saw that you looked at my breasts the other day when I told you to think sexual thoughts. I imagine they're even more stimulating this way. And besides, if you have another accident, it'll be easier to clean up."

He eyes were as big as saucers, and his cock was even bigger all of a sudden. Looked like it was working. Moving swiftly (I'd known some boys to spew without anyone touching them), I took the measurements and wrote them down:

Length: 6.52 inches. Girth: 3.76 inches. Growth since April 29: 0.22 inches.

It was bigger. Significantly. Damn.

Mouth dry, I reached out and rubbed his erection lightly. In a strangled voice, my cute son squeaked, "MOM!"

"We can't have you spurting all over me every time I measure your penis," I told him reasonably. "We need to work on your sensitivity. What if you were to go off before I got a good measurement tomorrow? That would impact our data here. Does that make sense to you?"

He nodded.

"Very good then" As I spoke, I encircled his cock with my hand—I could barely fit my hand around it—and started moving it back and forth as he gasped and shuddered above me. Very well, I have to admit it; I had an ulterior motive. My son's cock was in my hand, and I was loving it. I wanted to jack him off.

It didn't take more than ten seconds long before he was pouring his massive come load out all over his mother's aching tits. He didn't faint this time; he just swayed there above me, groaning loud and low. "There we are, then," I chirped, patting his still-hard cock, and went off to my room to clean up. I made certain to lock the door behind me.

Before I took a shower, I licked as much of his semen off my tits as I could reach, enjoying the sharp taste immensely. I let the rest dry on me to a crackling sheen as I dipped my seven-inch dildo into my wet cunt for the next hour, realizing, more than once, that at this rate it wouldn't be long before my studly young man's penis was larger than the dildo.

I'd have to get a bigger one, I decided.

Day 10. Length: 7.33 inches. Girth: 3.77 inches. Growth since May 5: 0.12 inches.

In order to maintain my cover story of helping him decrease the sensitivity of his hair-trigger orgasm, I had begun "working with" Tay every day after the second measurement. He was coming along nicely, I had to say, both on the length and stamina fronts. His girth hadn't increased significantly, but I figured it would. If this continued, he would soon be as thick as a soda can. His cock was ridiculously large for a boy his size; Tay stood well under six feet tall, and was slender as a girl. It looked as if some demented vivisectionist had grafted a porn star's cock onto my boy's crotch.

Definitely had to get a new dildo. The old one wasn't measuring up.

So far today, I'd been pulling on his cock for five minutes, and he was still gritting his teeth and taking it, so I figured I needed to throw something new into the mix. I slipped off my skirt, revealing that I was naked underneath and showing him healthy glimpses of my moist, sparsely-furred labia. His eyes widened, but to my amazement he didn't immediately spout all over me. I was impressed.

Ten minutes later, I was wondering if something was, in fact wrong with him. He was moaning softly, but where was the tasty eruption I'd come to look forward to? Frustrated, I leaned forward and took that big cock in my mouth. On my third pump he screamed and shoved it deeper into my throat, releasing a veritable geyser of spunk that seemed to fill me up from bottom to top. It spilled out of my mouth and dribbled down onto my taut nipples like a mini-Niagara.

Damn, it tasted so good to me.

When I could speak again, I said, "You're getting very, very good about holding back, honey. Congratulations. I don't think you'll need any more stimulation practice."

"Ahh!" he said, sounding panicky. "Mom, you're not just going to stop helping me, are you?"

I looked at him calmly, but my heart was racing. "But you can hold back for a long time now, honey. We can stop."

"I, I don't want to stop! I c-couldn't make it through the day without knowing you were going to..." he flushed deep crimson, "...um, you know, train me. I think I'd go crazy if you didn't."

"But what about when our experiment is over?" I asked, wide-eyed and innocent.

"I don't want it to be over," he mumbled, ducking his head. "And even when it is...I don't want it to be over."

"We'll see," I said.

He took a deep breath and nodded. "So...could we keep building up my stamina from now on with that...thing you just did?"

"I believe it's commonly called a 'blowjob.'"

"Yeah, that!"

"I think I can manage it," I told him, smiling inwardly. "It's for science, after all."

Day 20. Length: 8.4 inches. Girth: 4.2 inches. Growth since May 15: .10 inches.

Taylor's penile growth was advancing at a steady rate of a tenth of an inch per day. That may not sound like much, but if it continued at that rate, he would exceed a foot in length within weeks! I was beginning to be a bit worried. How was a slight boy like him going to be able to handle a monster like this thing was becoming? I'd thought him mutantly massive before, but this was getting ridiculous! But at last his girth had caught up to the length somewhat.

I was going to have to get another new dildo soon, I thought giddily.

I'd grown used to my daily protein shakes from young Taylor, but I'd discovered that, once again, he was becoming inured to the sensation. Oh, I could make him come all right, but it took a lot more time and effort now, and he was getting so big he made my jaws ache!

It was definitely time for something new.

By now, we both started our sessions completely nude. I glanced at my glistening crotch, which I knew my son was gladly ogling, and then at his glorious tool thrusting up at the ceiling. It was so large and heavy now that it no longer stood straight up, but rather ascended at a 45-degree angle. After long consideration, I decided that no matter much he turned me on, I wasn't ready for that ultimate act yet; but there was still something we could experiment with.

Leaning forward, I kissed the tip of little Tay's big penis, glancing up at him again. He was grinning, hardly blushing at all, and he thought he knew what was coming...but he didn't. I did open my mouth side and slide his cock between my lips, taking in as much as I could, deep-throating but unable to take it down to his sparse pubes, as I'd been able to do just a few days before. I made sure I slobbered all over his cock, getting it as wet and slippery as I could before pulling off it...

...and then enveloping his manhood in my titmeat."Baby, fuck my tits," I said breathlessly and crudely.

His eyes lit up, and he flushed deep crimson. "Omigod," he breathed, "I never ever thought of that."

I began to move up and down a bit, to prime the pump, so to speak. "There are four basic ways to make love to a woman," I told him, rubbing my nipples as he started thrusting hard into the crevice between my tit mountains, "and so far, you've experienced two. Can you guess the others?" I began to breath hard as the sensations (or should I say "sin"sations?) from my breasts connected straight to my cunt. I could feel my cunt drooling.

I dipped me head and licked his shiny glans as it popped up into my cleavage. He winced and said, "Vagina..."

"Cunt. Of course."

"And...and...anus?" I nodded. "R-really?"

"Really, son," I said softly, and his rhythm increased suddenly until, suddenly, he gifted me with a pint of his heavy cream, right into my open mouth. Of course it failed to stay here, dripping down and across my hot and heavy tits. I held his proud boyhood between my breasts, clutching it tight and pinching my nipples, rubbing my thighs together, until I was hit with shock after orgasmic shock, and all the tugging and gasping caused him to go off again, drenching me with another spray of semen just as thick and copious as his first load.

Once we stopped gasping and came back to ourselves, my son stroked my cum-soaked hair and said, "So are we going to train using those other ways later?" he asked.

"Well, you still need to learn to control your premature ejaculation problem," I quavered.

His sudden smile was like the sun emerging from behind a cloud, and I basked warmly in its glow.

Day 45. Length: 10.6 inches. Girth: 6.5 inches. Growth since May 19: .10 inches.

The kid was killing me.

For the past six days, my son had been "training" himself by plowing both my breasts and my mouth daily, at least once each, and what he'd told me five days before held true: he seemed to be able to orgasm repeatedly without losing his ability to recover his erection and manufacture ever more semen. I'm sure there was a limit somewhere, but I hadn't been able to find it. His growth and stamina certainly explained his enormous appetite; he ate enough every day to sustain a grown man twice his size. He had to, to fuel his other appetite.

Dammit, my jaws ached all the time now. Ever tried to deep-throat a monster cock for an hour at a time? No? Well, it affects your communications skills for the rest of the day, let me tell you. And my latest dildo just wasn't doing the job anymore.

It was time for the next stage in my little boy's stamina training. Past time, a little voice in my head said wickedly. Now, I had no illusions about what was happening here; the vaginal training, and then the anal training later, were unlikely to satisfy my son any more than the oral and tactile training had. They were stopgap measures at best. Oh, I would enjoy them—I was already trembling at the thought—and I doubted we'd ever stop fucking each other before one of us was dead. But a hypothesis was developing in my mind about my son.
My boy must have mistaken my hesitation for something else, because he said breathlessly, "Um, I think we should do oral training first, Mom. Okay?"

I shook my head sharply. "No, we've done the last of that. For a while anyway." At his heartbroken look, I continued quickly, "It's a matter of physical constraints, darling. I have a small mouth, and your girth has increased dramatically. It's almost impossible to fit you in my mouth anymore."

Now he merely looked disappointed. "However," I went on, "there are more....flexible options. I think it's about time we explored them." Standing slowly, I turned my back on him and then sloooowwwly lowered myself to my hands and knees. I thrust my bottom toward him and looked back at his glowing face, saying, "Now for the real test of a man: let's see how long you can last when it truly matters. How would you like to fuck Mommy's cunt? "

I used the deliberately crude terms just to stimulate him, or so I told myself.

He moved slowly forward, as if my pussy were a magnet and his tremendous dick were the bar of steel it so resembled in it stiffness. Soon, I could feel his cock riding atop the warm crack between my buttocks, and his hands clenching my hips. We were both trembling like first-time lovers, and I could feel the hot trail of his pre-cum oozing down onto my asshole. "Fuck Mommy's cunt, honey," I urged him in a strangled whisper. "Please!"

As though hypnotized with lust, he backed away slowly, and let his massive maleness inch down along the curve of my crack until the head was poised at the entry of my dripping cunt. Then, with a sigh, he eased his way in.

He was barely inside me, but I came so hard that he must have thought I was drying to wrench off the end of his cock. He pulled out, gasping, before he too could lose control.

"You fucking stud," I hissed when I regained my senses seconds later, the last pretence of my scientific detachment gone. "Fuck me! Fuck Mommy hard and deep, Tay-bear!"

Easier said than done. Despite my large practice dildos and the extra lubrication of my orgasm, it was slow-going at first; his cock was so thick it was simply difficult to fit inside. He eased his way in, groaning and gasping, and for my part I was chanting, "Don't you dare! Don't you dare come yet! Fuck me, baby! Fuck me hard!" Inside my head something was chattering inanely, My son my little boy my Taylor that's him inside me fucking me like the stud horse he is omigod omigod omigod and when he backed out and carefully thrust into me another come jolted through me like a white-hot spear and my pussy clenched around his hugeness and suddenly it felt like a sperm bomb had burst within me as he hosed my insides down with his incestuous semen. My son had lasted for two thrusts once he got inside me.

Bad, bad boy.

Of course, that's not a problem with a boy the likes of my Tay; the cum just became more lubrication for his big cock, and of course he stayed as hard as he always did. He started pumping into me vigorously, alternately gently and roughly, the whole time keeping up a dirty little mantra of "Oh Mom, your cunt feels so good, so good around my cock. I want to keep fucking you forever. I'm gonna fill your pussy up with more of my come, fuck I love you, I love your pussy, I'm the luckiest boy alive, OH MOMMMMMMMYYYY!"

That last outburst was accompanied by another outburst inside me, and I came so hard as his cock provided delicious friction against my cunt walls and clit that I blacked out. When I came to I was still propped up on hands and knees, and he was plowing on, crowing his delight in an unending spiel of innocently filthy sex talk that made my erogenous zones tingle with delight.

I lost track of how many times we came that day. But I do know that after an hour or so my knees got so sore we retired to his bedroom, where we proceeded to have sex in a variety of positions for five full hours more. That's right, it was another five hours before he was literally fucked out, so exhausted that he couldn't move. I'm not sure, but I think he could have gotten it up again if he'd wanted.

By then, I was sure about my hypothesis. I had decided that young Tay wasn't ill or even abnormal, except in the sense that he was a cut above most males. In truth, I was beginning to thing he was that sexual rarity, a superpotent—one of those males that no single woman could ever satisfy, who could keep going and going and going as long as he could remain conscious. Eventually, I would need to find other women for him to fuck if I wanted to get anything done.

Until then, though, he was mine, and I didn't care to share. I knew I would eventually have to, though, because even a horny woman can only take so much, and to do without would be detrimental to the poor lad.

In any case, he woke me up with his cock buried deep in my cunt the next morning, and we had a long, slow fuck before we ate breakfast. After he downed enough for two grown men, he was ready to go again. We both had a shower together (we needed it by then), and of course we screwed there, too. Then we went back to bed.

Late that afternoon, after another massive meal, I experimented with letting him ease that huge thing into the tiny pucker of my asshole. We managed it with a lot of lubrication and care, but he was so big I didn't dare let him fuck me there. So after another shower, I showed him what he needed to do to pleasure a woman, and he turned out to be a first-rate cunt-lapper and tit-man. Then we made love until late into the night.

We were so busy that neither of us remembered to measure him, but I could tell as his enormous member flexed within me that he was still a growing boy. My growing boy.

Day 67. Length: 12.85 inches. Girth: 8.7 inches. Growth since July 25: 0.001 in.

It seemed that my son's insane penile growth had more or less stopped. Alas, his sexual appetite had not. In fact, it seemed to be increasing, heaven help me. I was pretty much exhausted. We had sex no fewer than four hours a day, and I had begun to have to send him away so he could masturbate alone, which neither he nor I liked.

After setting aide my measuring tape away, I gave Taylor Jr. an affectionate pat and said, "Honey, I'm afraid you'll need to put the monster away for a bit and get dressed. We've got company in a few minutes."

"Awww!"

"Tay-bear, I'll make it up to you, honest I will. Just get dressed...and do your best to rein that thing in. We can't let people see you with a huge erection in your pants."

"Okay," he sighed, and retired to his room. By the time he emerged in the sitting room, dressed in a neat Oxford and slacks, he looked like your normal young man, handsome and slight. Admittedly, his slacks were a bit capacious; I've had to get them specially tailored, given his incredible size. But no one would notice that unless they really looked.

I was dressed in a simple dress that could come off easily. Sitting beside me were two women, one a bit older than I, and one in her mid-twenties. "Hi, Aunt Joan," Tay said, hugging my sister. He looked at the other woman curiously.

"Don't you recognize me?" she asked. "It's Miss Tina, from eighth grade."

"Oh yeah!" he burst out. "I had such a crush on you! How are you?"

She blushed prettily. "Oh, I'm good. Very, very good."

My boy sat down on the armchair across from where the other girls and I were sitting. "What's up?" he asked guilelessly.

I glanced at Joan, and we grinned. "I've heard that you are, young man," she said, in her earthy contralto. Taylor has always had a thing for his sexy aunt, and he turned red as a beet.

"Mom! he protested. "How could—"

I cut him off. "I love you more than anything, Tay-bear, but you're more than a single woman can handle. So I recruited your aunt and Miss Tina to help me with your, um, 'training.' Joan has been telling me for years that she was going to take you to bed as soon as you were old enough. I thought she was joking...but it turns out she wasn't. As for Miss Tina, well, several of my younger patients have told me about her fondness for teen boys...so I approached her. Needless to say, once they heard about your fantastic cock, they just couldn't wait to help us."

Tina crossed her legs lasciviously, making Taylor very aware that she wasn't wearing panties, as his aunt tugged down her top to display the full glory of her breasts. As for me, I reached down to the hem of my dress and pulled it up and over my head, revealing my full nudity.

"For now," I told him as I lay back and dabbled my fingers into my steamy cunt, "we're going to train you as a team. What do you think, baby?"

"I think I can live with that," he said, grinning. Without being invited, he unzipped his slacks and fished out his cock, which was already ballooning to its full monstrous size. My little man was finally getting over his shyness!

I sat back to watch as my sister fell on his huge cock like a starving woman attacking a steak, and Tina crouched over his face to receive his tongue, her eyes glued to the 13-inch pillar of flesh between his legs as Joan worked to get her lips around it.

Good Lord, I was in heaven.