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The Apothecary had been very clear on how Marius was supposed to handle his current situation: rest.
At first, the prospect of some daemon presence making his body into its incubator had been enough to keep him up at night, but the repeated examinations had made it very clear that the strange mass inside him was entirely natural. Gene-seed, as perfect and infallible as it was meant to be, still relied on the recipient being perfectly compatible with the changes it offered.
Something about Marius’ biology had evidently caused a few unforeseen problems .
Redoing back in the creaking chair beneath him, the half-disrobed marine ran one hand over his newly-rounded middle, his breathing steady but slower than normal. Only a week ago, he had been marked down with a clean bill of health, but he already looked as though he had spent the past six months carrying a baby to term.
As his hand pressed against his stomach, Marius could feel the tightness of his skin, which had quickly stretched to accommodate the growing mass within. His muscles had always been firm and toned, but the pregnancy had caused them to overstretch their limits in a way that utterly ruined their definition, taut skin pulling tight over what was once a washboard stomach. Each brush of Marius' fingers against his belly elicited a groan from the back of his throat, a twinge of pain firing off to his brain every time the oversensitive surface was pressed just a little too hard.
The Apothecary had advised him not to exert himself too much, but the constant need to adjust his armour and equipment had been a challenge, forcing Marius to make some adjustments to his wardrobe. Namely, he had needed to discard anything that threatened to squeeze his rounding stomach too tightly, and that meant switching out his chestplate for some off-duty robes. Helmet, gauntlets and boots all remained, but only because he already felt like he was merely a step away from wearing maternity clothes - a thought that gave him a confusingly mixed set of deep-rooted feelings.
Marius knew the Apothecary would want him to lie back and let the growth progress to a point where something could be done about it, but it was simply not in his nature to sit idle. It wasn't exactly easy to find entertainment when you were bedridden and unable to do much besides look out a window, or read a few books. Nobody wanted to let him do anything potentially harmful, and that had left him feeling like little more than the Chapter's prized incubator, even if their intentions were good. That, and even in the absence of physical activity, the uncontrolled hormones raging through his body had left him with a constant, simmering need for release that he refused to indulge.
Grunting against as he felt the mass inside him kick again, the frustrated Astartes tried his best to ease the tension. Reclining back only made it even more obvious that he was obscenely stretched he actually was, his newly-bulging gut jutting out far enough that it blocked an easy view of his knees. Marius had always been proud of his size and strength, and to feel so full and useless was a humbling experience - especially given how that beyond-human size translated into a beyond-human late-stage pregnancy belly. The worryingly-frequent occasions where a serf had come to check on his condition has given Marius a perfect point of comparison, and watching them take their measurements had only made it blatantly clear that he looked as heavy and swollen as he felt.
At this point, he had stopped asking for updates on exactly how big he was. Seeing two serfs struggle to wrap their arms around his waist had been a humiliation too far.
As he leaned back in his chair, Marius' fingers traced along the underside of his stomach, the stretched-tight skin so sensitive that even the lightest touch was almost unbearable. The constant need to relieve the pressure was driving him insane, every twinge of his overburdened insides a reminder that there was nothing he could do to ease his condition. Every so often, the gene-seed-crafted mass in his guts would punch out again, making him gasp as his stomach lurched and kicked outwards, his skin tightening around the protruding bulge in a way that only added to his discomfort.
It was almost impossible to deny the arousal he felt at his own predicament, though. Even before the pregnancy had started to show, Marius had always enjoyed some measure of self-indulgence on the rare occasions where the Emperor's omnipresent gaze felt approving of it, but this was on a whole new level. A not-insignificant part of his mind was enjoying the sensation of being so full and heavy, and the lack of any responsibilities had given him the perfect excuse to indulge.
As he was, Marius was a far cry from the man who had stood fast against Ork hordes time and time again, or the man who had personally beheaded a heretic cult leader. Within one week, he had turned into a plump, heavily-pregnant mockery of an Astartes whose swollen belly seemed to grow by a factor of inches per hour. It was almost humiliating how little effort it took for him to lose his breath at a gentle waddle down the Fortress-Monastery's corridors, let alone the way that his gravid middle that he could barely hide behind even the loosest of off-duty robes.
He didn't understand why he was enjoying it, but the sensation of his stretched-out skin tightening with each movement was driving him mad.
Letting out a frustrated huff, the overly-taut Astartes tried his best to sit up straight, his rounded belly forcing him to awkwardly rest one hand against the upper curve as the other gripped the armrest to hoist him up. Even for an Astartes, the sheer heft nestled in his gut made it a challenge to do anything except lie back, the movement compressing the growing mass within and making him feel more bloated than ever.
As he finally managed to haul himself upright, Marius couldn't help but turn his gaze to the mirror on the wall to his left, a shaky breath leaving his throat as he saw just how huge he actually looked. The robes had been a poor fit to begin with, but this afternoon alone had seen him stretch them out even further, the fabric tightening to the point that they didn't even obscure just how obscenely gravid he actually was. Without the comfort of lying back in his chair, he was forced to feel the added weight and stretched skin, the mass inside him pushing out violently as a response to how much it had just been jostled.
It was going to be a long, slow gestation period.
—
Marius hated how much he loved his situation, and the Apothecary's sheer confusion at what was happening had only stirred up more mixed emotions. On one hand, the situation was bad on multiple levels, both in regard to himself and the potential for more gene-seed to mutate in the same way. On the other, the Astartes had been constantly fighting indecent erections every time he thought about how far things could get out of control.
Something about the prospect of having to wander the Fortress-Monastery's halls looking heavily pregnant and ripe to pop had unlocked a side of his mind he had never known existed.
He had started to relish the stares of his battle-brothers as he moved to and from the Apothecarium, the exasperated attempts by the quartermaster to find robes that would cover him properly, even the way that he had begun to feel heavier with each passing day. Through it all, there was one constant that he was starting to enjoy just a little too much, and that was how quickly the mass inside him was growing.
At first, he had been able to endure it mostly fine, the initial week offering little more than tender skin and slight discomfort. Not even four days later, his skin had reached the point where it wasn't able to distend as quickly as his stomach grew, the tightness of his stretched-out skin becoming a constant presence. He looked like he was rapidly approaching the eighth month by human standards, but absolutely nothing about the situation felt like it was coming to a head soon - and that meant made the stretch marks and overly-taut sensitive skin even more distracting.
The Apothecary had been trying a range of options to deal with the situation, but nothing had come to fruition, and Marius was almost relieved. At this point, he didn't want things to be over so soon - the way his breath hitched and wavered whenever he ran his hands across the tightened, visibly-bulging skin of his own overfull pregnancy belly was almost addicting, not to mention the fact that he was starting to full out too much to fit his entire body into the mirror. His chest had begun to swell in response to whatever cocktail of hormones and signals had been plaguing his entire body, like it was trying to force itself into a crude copy of late-stage motherhood.
As he stood up from his now-clearly-unsuitable chair, Marius had to bite his lip to stop himself from moaning at the way his stomach pressed up against the fabric of his robes, the mass inside him stirring as the shift in gravity got the gene-seed amalgamation riled up. It was getting harder and harder for him to hide how much he was enjoying the sensations, especially given that the thing inside him seemed actively upset that it was being kept contained. The Apothecary hadn't been able to explain anything about what was happening, but if one thing was clear, it was that the growth was still accelerating regardless of what treatments Marius tried.
A part of him knew that should have been a cause for concern. Another - much larger - part of him was obsessed with the feeling of his hands resting against the taut, stretched-tight skin of his pregnancy belly as he felt the mass inside him stir and press outwards against its confines.
He couldn't explain it, but the more his body changed, the more he found himself enjoying it.
Marius wasn't sure how long he had spent in front of the mirror, just watching as his hands traced along the upper curve of his belly. Every time he moved, the sight of his stretched belly bulging and squirming from the frustrated movements of the mass inside it out was a sight that made his heart race and his cock stiffen in his pants, a mixture of shame and arousal rushing through his body in equal measure. At this point, his makeshift maternity robes were more of a suggestion than actual clothing, the fabric stretched tight over his bulging stomach and rounding chest to the point that they only accentuated how heavily pregnant he actually looked. Each brush of the fabric against his oversensitive skin sent a shudder through his entire body, the inconsistent leaking of his tender nipples only making the problem worse if he dared try to cover up his chest.
With a groan, the Astartes leaned back, his head tilted back as he felt the mass shift and churn beneath his hands. It had gotten so huge that even the slightest movement was enough to send a cascade of signals to his brain, each kick and shift of the gene-seed amalgamation making him gasp and groan as his body responded in kind. The sheer weight of his overfull belly had made him feel like he weighed twice what he had a month ago, and it was only getting worse by the hour.
He could feel his mind starting to slip, the constant mix of hormones and arousal clouding his thoughts and making it hard to focus. The only time he felt anything resembling clarity was when he was running his hands across the overstretched skin of his pregnancy belly, feeling the tightness and heaviness of the mass within as it slowly but surely forced him to - and then past - his limits.
As he leaned back in his chair, Marius let out a low moan, his breathing ragged and uneven. His chest had started leaking a thin stream of milk a couple of days prior, and it hadn't stopped since, the fabric of his robes stained with damp patches where the liquid had soaked through. The constant leakage was both incredibly uncomfortable and incredibly arousing, the sensation of his tender, swollen nipples pressing out against the fabric a constant reminder that something about his predicament had awoken a part of him that he had never expected.
—
The Apothecary had assured Marius that it would be over soon, but the lack of any visible endpoint to his rapidly-progressing pregnancy had left him wondering what could happen next - or, more specifically, craving to find out.
The thought of his belly continuing to swell, his chest continuing to leak and his body continuing to grow was intoxicating. Marius wanted to watch himself round out further in ways he could no longer even attempt to hide, wanted to see his perfected body utterly ruined by a neverending pregnancy. Even walking through the halls had become thrilling in its own right, his battle-brothers looking at him like he was an oddity to be gawked at - a genetically-sculpted warrior of the Imperium turned into a pregnant sow that constantly seemed primed to burst.
The constant shifts and changes in his body had been a never-ending source of pleasure, his gravid belly pressing out further and further each day. With every shift, his robes stretched tighter and tighter as did his skin, his stomach demanding his hands for support and forcing him to walk with a pronounced waddle. He had gone from a proud, muscled warrior to a heavily-pregnant incubator that could barely even squeeze into the Apothecarion's examination chairs.
Even when he was alone, Marius couldn't help but watch the way his body expanded in real-time, the mass inside him shifting at even the slightest disturbance. Uneven and unpredictable bulges kicked out at seemingly random times, the amalgamation within clearly frustrated by its inability to fully stretch its newfound prison. It hurt as much as it satisfied some desperate need in a primal part of his brain, and Marius found himself unable to look away, his breathing heavy and uneven as his hands traced along the taut, stretched-tight skin.
Every day, he had gotten a little bigger. Every day, he had started to enjoy it a little more.
At this point, he could no longer hide it from the rest of the Chapter, the constant need for new robes and the sheer size of his pregnant belly making it obvious to anyone who saw him. There was no hiding how badly he was struggling, no hiding the constant twinges and groans and shudders that wracked his body as the mass within demanded more room. Given that they seemed to be far less concerned about his situation, he had to assume that they had finally realised his moans of discomfort were anything but.
He was filling out far too much of his own mirror - and, for that matter, his quarters as a whole.
Every time he lay down, he could feel the weight of the mass inside him shift and churn, the amalgamation growing more and more irritated with its inability to expand. Even a cursory glance could see the way the taut skin was stretched tight and bulging around something it was barely able to contain, a problem that had only gotten worse thanks to the bizarre amniotic-fluid-like substance being generated in whatever space remained. The pressure was starting to become unbearable, and it was only getting worse with each passing day, the constant need for release building up until Marius could no longer stand it.
Today had been the day where his limits were finally reached.
With a shuddering groan, the Astartes slid one hand down the lower curve of his belly, the stretched-tight skin bulging around his fingers as he felt the mass shifting and churning within. His chest was leaking even more now, the fabric of his robes soaked through and stained, his nipples red and sore from the constant stimulation. Everything about his body was sending a mixed set of signals to his brain, the mixture of pain and pleasure a confusing haze that threatened to consume him whole.
He had never thought he could reach this point, but here he was, his overstretched skin bulging and shifting around his hand as the mass within responded to his touch. He was achingly overfilled, completely exhausted and diamond-hard all at once. He couldn't remember the last time he had felt so needy, so desperate, so utterly lost in a haze of pleasure and frustration.
As he ran his hand along the lower curve of his belly, Marius couldn't help but groan, his breathing ragged and uneven. The sensation of his overfilled gut straining and shifting as the mass within continued its desperate attempts to expand was almost too much to bear, his free hand gripping the armrest of his chair tightly as he leaned back. Every twinge and shudder and groan was like a lightning bolt to his brain, his senses heightened and overstimulated, the slightest shift making his breaths falter into gasps.
The entry chime to his quarters sounded off, the door sliding open as a familiar serf entered with an understandable amount of hesitation. Emil had been a regular visitor within the last few days, barely speaking but dutifully tending to Marius’ needs - presumably under orders from the Apothecary. The Marine had barely noticed, his eyes fixed on the shifting bulge in his own belly, the sight of his body straining and stretching and swelling in real-time.
"Master Marius," the serf began, his voice low and tentative. "I was asked to check on your condition."
It took the Astartes a few seconds to respond, his voice a shaky breath as he forced himself to focus.
"I am fine," he grunted, his hand still resting against the bulge in his belly. "Or, at least, as fine as I can be."
The serf looked nervous, his gaze lingering on the Marine's heavily-pregnant stomach.
"The Apothecary asked me to measure you again," he said, his eyes drifting downwards. “There may have been a significant increase since yesterday."
"I can-“ His voice cut off into an unrestrained groan as the mass inside him lashed out, his overfull belly literally having to distend a few inches beyond its limits to accommodate the amalgam's sudden shunt forwards.”…Ngh, I can see that from here.”
The measuring instruments were wrapping around him mere moments later, the poor serf struggling to wrap the tape around the marine’s gravid gut in a way that didn’t cause an errant moan to slip out. As his hand brushed against the overstretched skin, Marius couldn’t help but let out a shuddering gasp, his entire body trembling at the contact.
"Master Marius," he stuttered, his voice wavering. "You are not… not meant to be this big. The Apothecary estimated that-“
"I am well aware of the Apothecary's estimate," Marius growled, his voice low and raspy. "But it is not up to him. It is up to the… the..."
As the serf withdrew his instruments, Marius' words trailed off, his eyes widening at the sight before him. The measurements hadn't come as a surprise, but seeing the tape wrapped around his own belly made it impossible to deny the sheer scale of his situation. The Marine was massive, his belly stretching out so far that he could barely even fit into the chair anymore, his gravid stomach protruding far beyond the armrests even if he tried to lie back. At this point, downplaying how obscenely huge he looked would have been nothing but denial, and there was no way he could hide it now.
The growth was accelerating faster than ever before, his overstretched skin pulling taut and strained around his over-engorged stomach, his entire body struggling to contain the mass within. The sight of his taut, overfilled belly jutting out from his robes made him look more pregnant than any human woman ever could, his chest swollen and tender and his hips visibly widened to accommodate his passive weight gain now that he was eating for two and barely leaving his room.
As the serf withdrew, Marius couldn't help but lean back, his eyes wide and his breathing ragged and uneven. Everything about the situation was starting to become too much, his mind swimming with a haze of mixed emotions and sensations. He had never thought he could end up like this, his body utterly ruined by a gene-seed mutation that had turned him into an oversized incubator for a mass that could only continue to grow. It was insanely arousing in ways he didn’t fully understand, but the feeling of his hands against his rounded stomach and his chest leaking a constant stream of milk had awakened something inside him that refused to be ignored.
Emil turned to leave the room, his eyes fixed on the floor.
"I will inform the Apothecary of-”
" Wait ."
The word was out of Marius' mouth before he could stop himself, his breathing heavy and uneven. The serf turned back, his expression confused.
"I am sorry, Master Marius. Did you want something else?"
"Stay," the Astartes could feel his heart hammering in his chest at even the idea of what he was about to ask for. “I… require some relief.”
—-
Marius looked ripe to pop.
The Astartes’ pregnancy growth had entered what felt like the twelfth month of a nine-month pregnancy, his gravid gut so swollen that it was hard to believe it was actually part of his own body. The taut skin was stretched tight and flushed red alongside deeper-crimson stretch marks, the mounting pressure only adding to his desperation for a release he wasn’t sure he could get. The fact that the mass inside him seemed intent on expanding regardless of his own comfort was almost overwhelming, the sheer size and weight of his pregnant stomach making it impossible for him to stand without support.
Even lying back in his long-suffering chair as it creaked under his weight, the Astartes stared halfheartedly at the syringe in the serf’s hand.
“He… what?”
“He has found a solution.” The serf nodded, his eyes fixed on the floor. "The Apothecary believes the issue may be an imbalance of hormones, Master Marius. This syringe contains a mixture that should rapidly, ah… resolve the problem. Harmlessly and painlessly, with only a few days of bedrest required.”
Marius looked at the syringe, his breathing unsteady. He knew the Apothecary had been researching ways to resolve his situation, but he hadn’t actually expected a direct cure to the gene-seed mass swelling out of control inside him. A part of him knew he should be relieved, but another - a much larger one - was disappointed. He had spent the past month reveling in his own transformation, but he was basically obligated to accept the cure at this point.
The serf took a step forwards, his hands shaking slightly as he held out the syringe.
"Master Marius, are you alright?"
The Astartes took a deep breath, his eyes fixed on the serf.
"No," he growled. "I am not."
His fingers tightened around the armrest, his breathing ragged and uneven. The mass inside him stirred, the movements almost violent in their intensity. He could feel it pressing out against his stomach, forcing his belly to strain and shift with every movement. He couldn’t deny how good it felt, how utterly intoxicating the sensation of his own body shifting and swelling and growing was.
The serf took a step back, his face pale.
"Master Marius," he gulped. "I'm sorry, but you are not thinking clearly. You must take the treatment and-"
"I do not want it," the Astartes growled, his voice low and raspy. He didn’t know why he was so passionately against the idea, but something inside him was demanding it. “Not… not yet. Put it down somewhere. Anywhere.”
"Master, I cannot just-"
"Please."
The serf paused, his eyes darting between the syringe and the Astartes. The pleading note in Marius' voice had caught him off-guard, the Astartes' desperation enough to override his own sense of duty.
"If I did not have direct orders from the Apothecary, I would not- "
"I do not care about the Apothecary's orders. He isn’t the one who’s had to live with this… thing… inside him for the past month." He patted the upper curve of his overdue-looking belly, immediately regretting it as the gentle touches sent a surge of pleasure straight to his brain. "...nhg, one more night, just one.”
The ‘ with you’ was silent, but Marius hoped that his tone made his request clear. If he was going to go back to being his usual self, he needed a chance to savor the moment while it lasted. His serf had helped him ease his aches on occasion, but he wanted to go all out just this once.
"If the Apothecary found out, if any of your brothers saw, I could be-"
"He will not. No one will know." The Astartes took a deep breath, one that faltered as the mass inside him kicked out again. "I promise."
There was a long silence, the serf's eyes fixed on the syringe.
" Alright ."
The next few moments felt like a blur. Before Marius could even fully process the word, Emil had set the syringe back down in its protective case and left it on the bed, moving over to the Astartes and immediately reaching out to stroke one hand across his gravid stomach. Marius couldn’t help but groan at the sensation, the mass inside him stirring in response. He had barely been touched in the last few days, his constant need for attention and his body's own natural sensitivity driving him insane - and his own hands felt nowhere near as satisfying.
"You’ve grown again. " Emil's voice was low and reverent, his hands moving across the Astartes' heavily-swollen stomach. "A lesser man would have burst.”
The serf's hands moved downwards, slipping beneath the Marine's now-pointless robes and tracing along the underside of his bulging belly. The feeling of his skin straining and stretching to contain the mass within made Marius feel almost faint, his mind swimming with a mixture of shame and arousal. It was insane, but he was so addicted to the sensation that he couldn’t imagine going back - he had to relish the feelings while he still could.
As the serf's hands moved down below his navel, his fingers tracing along the overstretched skin, he couldn't help but shiver. His chest was leaking again, the flow restarted by the stimulation, and he could already feel the wetness spreading outwards from the fabric of his robes. He knew he couldn’t hide it, and a part of him didn't want to. He wanted to be exposed, to show off the changes his body had gone through, to have others worship and degrade him in equal measure.
The serf's hands pressed out against his stomach, his touch gentle but firm, and the Astartes couldn't help but groan. He could feel the pressure building up within, the mass inside him squirming and kicking as his body struggled to accommodate the sudden stimulation. Every shift and movement felt like a lightning bolt to his brain, his breathing ragged and uneven as the serf continued to trace his hands over the Astartes' heavily-swollen midsection.
It wasn’t long before one of the serf’s hands took hold of his chest instead.
Marius had been so engrossed in the sensation of his overstretched skin tightening around his belly that he hadn’t even noticed the serf's other hand until it had already taken hold of one of his pecs. The Marine couldn’t help but whimper at the contact, his nipple leaking a thicker flow stream of milk almost instantly. The serf didn't hesitate, his fingers gently easing out the pressure that had been building up within, and Marius couldn’t help but shudder and gasp, his entire body wracked with the most intense pleasure he had felt in weeks.
"I’ve never seen anybody so… so… laden . So heavy.” the serf murmured, his eyes fixed on the Marine's bulging, obscenely-pregnant belly. "And so, ah… fertile."
Marius couldn’t even respond, his body wracked with spasms and shudders as the serf continued to gently milk him. The feeling was like a lightning bolt to his brain, his body overstimulated and oversensitive to the point where even the slightest touch was enough to make him lose control. He had never felt so good, so desperate, so utterly lost in a haze of pleasure and need that refused to let him go.
Shuddering out a huff to clear his throat, the Astartes tried to keep his breathing under control.
“My… my stomach is-“
“You mean, your womb .” The tone in Emil’s voice was outright teasing, but still held behind a layer of duty bound professionalism. “The only word befitting of your current state is womb, Master Marius.”
There it was - the word that finally punched out any sense of denial left in his mind. It was one thing to waddle around with a belly full of mutating gene-seed - but the moment his brain tried to reframe it as a womb full of gene-seed, it was like he had just had a hundred individual fetishes unlocked in the back of his mind all at once.
"It is not my… my... ohh ..."
The Astartes could barely finish his sentence before the mass inside kicked again, this time so hard that his overdue-looking belly visibly bulged outwards in various places at once. He could feel it pressing out against the serf's hand, the gene-seed construct inside him trashing out against his inner walls, and the sensation was enough to make him gasp and groan, his entire body tensing up and his thoughts clouding over.
As Emil's hands continued to explore every inch of Marius' pregnant form, the marine could feel himself losing control. He was completely helpless under the man's touch, his ragged breathing collapsing as his body reacted to the constant stimulation. He was a mess, his chest leaking and his womb stretched to its limits and his cock aching against the wet patch that it was leaving beneath his robes.
Marius wasn't just enjoying the physical sensations working through him, but the intent behind them - the fact that his serf was willing to touch him like this, to bring him to such a desperate, needy state. He knew it wasn't exactly professional, or proper, but he couldn't help it - the sheer size and weight and obscenity of his belly was just too much for him to resist. The sensation of his overdue-looking middle straining and stretching and shifting before his eyes somehow made things both better and worse, his unrequested arousal conflicting with his wavering resolve to keep himself pure of daemonic influence.
"Emil," he groaned, his voice raspy and uneven. "I cannot… cannot contain it much longer. I..."
The serf responded by sliding his hand down between the Astartes' legs, the motion eliciting a choked gasp from the Marine. As his fingers brushed against Marius' cock, he couldn't help but shudder, his oversensitivity working against the legendarily-impeccable self control that Astartes were supposed to possess. The feeling of his serf's hand tracing up and down his length was overwhelming, the pressure building up below his belt almost rivalling the pressure continuing to mount in his womb.
Stomach, not womb. He couldn't afford to think about it that way.
But it was already too late. As the serf began to pump his cock in earnest, Marius couldn't help but lose his sense of shame, his body reacting faster than his brain could register. He was thrusting his hips up into the serf's hand, his eyes shut tight as his chest leaked and his belly squirmed, his entire body reacting to the stimulation like a coiled spring ready to snap. It was insane, it was obscene, it was everything that would normally have earned a very quick and painful death from the chapter's Chaplain - but here and now, in the privacy of his quarters, it felt like the only possible way to release the tension building up within.
Marius had been around daemonic artifacts and their worshippers many times before, and there was always a familiar taint, a perceptible darkness to their aura. The same couldn't be said for his situation - and whether that meant he was truly free of Chaos influence or already too under its spell to notice, he wasn't in any state to stop himself from digging that pit deeper.
Before he could even fully register what was happening, the Marine had started to cum, his back arching as his hips jerked forwards, his legs stiffening straight and his chest heaving as his mind was flooded with a cascade of signals that overwhelmed any sense of reason left within him.
When he came, it was like nothing he had ever experienced.
The sheer size of his stomach meant that he had already felt his overburdened womb struggling to contain the gene-seed within, but now it was pushing outwards in a series of spasms and shudders, the liquid release filling the Marine with an overwhelming sense of relief and release that contrasted just how painfully over swollen he was. The pressure had built up for so long that it was almost euphoric to finally let it go, and the sensation of his stretched-out skin distending around his rapidly-growing baby bump was more than enough to drive past that point of no return.
The rapid, uncontrolled bucking of the Astartes' hips clearly caught the serf off guard, his fingers tightening around the base of the other man's cock and letting the marine empty himself onto the lower curve of his own swollen stomach. Each pulse of pleasure that ran through him forced out another spurt of seed onto his master-crafted robes, the overstimulation causing the mass in his womb to writhe in confusion.
By the time he finally collapsed back in his chair, panting and spent, Marius was a mess, his laboured breathing filtered through his helmet. Emil took a few steps back, his hands shaking slightly as his gaze shifted between the Marine's bloated, heavily-swollen belly and the streaks of seed staining his robes.
"...I... will return with some towels , Master Marius."
The Astartes couldn't muster a response, his brain swimming with a haze of mixed emotions and sensations as he watched the serf nervously skitter out of the room - clearly having just realised what he had done and terrified that he had overstepped his station so severely.
For a moment, the only sound in the room was the Marine's own breathing, ragged and uneven. As his hand brushed against the upper curve of his gravid-looking belly, Marius couldn't help but shudder, the sensation of his overblown womb sending a cascade of signals to his brain that threatened to overwhelm him. He knew he couldn't let this happen again, but a part of him didn't care - his need for release was simply too much for him to ignore, especially now that a glance down confirmed he could no longer see his own cock past the obscene swell of his middle.
He would have to take the Apothecary's solution in the morning. No more hiding, no more lying, no more trying to deny what his body was telling him. He needed to get his situation back under control, even if it meant denying himself the sensations he had been craving for so long. Tonight would be a night of devout prayer, careful reflection, and begging for the Emperor's forgiveness.
That's what he told himself , at least.
A gentle brush of his hands across the lower curve of his bloated, obscenely-swollen stomach was all it took to make the alternative a lot more tempting.