Archive of Our Own ^beta

Optimus sighed defeatedly as he made his way into the farm. He and Bumblebee made sure every barn was clear of damage and stocked full of hay that gleamed with the energon within.

They had to be careful, the cows and bulls were now at the cusp of their mating season, which meant he had to let the cows out of the barn and into the fenced field to mingle with the bulls in there to find a suitable mate.

He somehow still felt new to the life of a farmer, even after all the deca-cycles that had passed since he inherited the farm from Alpha Trion. But he had experience in helping around the farm when his old guardian needed another set of servos.

His worries, however, did not stem from that old anxiety. Rather, they originated from a specific mechanimal on the farm.

Megatron, the bull that Optimus selfishly favoured above the others, was nowhere to be seen in the far stretches of the land where cows and bulls have already commenced their mating in the open. The bull was very much a loner, even as his strength lent him the admiration and reverence of other bulls. He would usually trudge the borders of the land or even indulge Optimus in petting and grooming him, preferring that to the company of his fellow bulls and, even surprisingly, the advances of various cows.

This solitary attitude seemed to hinder his mating, as he refused all cows that Optimus introduced and attempted to pair him up with. That caused a problem as Optimus did not wish for his precious bull to go at it alone in the mating season on the eve of his coming of age.

With each cow that Optimus unveiled, from the big, strong cows that were heavy with milk to the sweet demure ones that mooed suggestively at him, Megatron would chuff and roll his optics away, pinning them to Optimus with a hard stare, as though accusing him for his unimpressive picks of Megatron’s mates. Megatron’s frustration was clearly growing as the season was coming upon them.

Optimus scolded himself internally. Megatron was right, he should know what type of mate Megatron needed after all these cycles.

Optimus had personally taken care of him after he was rescued from an abusive farm and relocated to his own due to its good reputation with rescue cases in the past. The small bull was horribly malnourished, with dents and scuffs littering his jerking frame—a lingering effect of the electric sticks that were used on him to correct behaviour. He was in his quadrupedal alt mode all the time, huddling into any corner he could squeeze himself into.

The poor thing was scared of anything that moved, his grey-as-death frame would freeze up if anyone approached him. The only identifying feature on him was the ear tag with his designation, D-16.

Optimus had spent a considerable amount of time trying to coax the little bull into accepting his aid. He would offer treats and praises wherever he could. The day that a small helm pumped his servo and he looked down to see D-16 in his bipedal alt mode for the first time, leaning into him and silently asking for pats, was a day that Optimus wouldn’t forget for the joy it brought him.

Soon, D-16 became inseparable from his side, nudging and huffing at Optimus whenever he came around to the bullpen, wanting to get his attention and soothing scratches behind the ear.

Optimus decided to give D-16 a proper designation, one befitting the majestic bull he knew the little one would grow to become. He chose the designation of one of the fabled heroes of old. And so he settled on Megatron.

Breaking out of such musings, Optimus looked around, searching for Megatron‘s signature silver armour. The bulls and cows were getting rather loud with their interfacing. Some bulls were rutting into their mates in their quadrupedal alt mode furiously, only searching for their finish, while others were being more intimate and fragging their chosen cow languidly, utilising their bipedal forms to kiss and change positions at will.

He did not wish to be a voyeur, but he needed to find Megatron. He decided to circle the fence, thinking that if Megatron had already picked a mate, his lonesome nature would make him decide to interface with the cow in a secluded spot away from the others. Optimus just needed to see that Megatron was alright and wanted for nothing.

After a while of walking the border of the land, and as he reached the opposite side of the farm proper, he was shocked to find a part of the fence collapsed. The size of the damage was enormous, fit enough for a giant bull to waltz through.

Optimus panicked. This could only be Megatron’s doing, as there were no other bulls strong enough to rend the thick metal fence this way. He frantically looked back at the bulls and cows to see them busy with their mating, and too far away to see the open hole in the fence.

Optimus concluded that his priority should be to find his missing bull. He hurriedly inspected the scene to find giant hoofprints leading to the forest.

As he ran after the trail of hoof-shaped indents, he commed Bumblebee to let him know that he should call for repair for the fence as soon as possible.

By the time Optimus found the bull near a creek, the sun was setting, bathing them in dusk.

Megatron’s form was nestled underneath the shade of a giant tree. His tail restlessly thumbed the ground even as he seemed to be recharging.

As Optimus drew near, the sound of his pedesteps alerted Megatron to his presence. The bull instantly shot up and nailed his gaze on the intruder.

“Hello, Megatron. You have caused quite a bit of trouble for me by breaking the fence and leaving the safety of the farm like that,” Optimus said, softening his tone as panic slowly left his frame. He cautiously drew near to the bull, raising his servos in a placating manner.

Megatron’s faceplate brightened as he registered who was approaching him. He stood to his full height and trudged to his caretaker. His jubilant walk was a stark contrast to his intimidating frame. His sharp horns and gleaming, thick silver armour had always been enough to scare away any rivalling bull.

Optimus smiled at the sight. His dear bull will always be a child at spark, his excitement always on display when he is alone with Optimus.

He took out a cube of energon from his subspace. Lifting it for Megatron’s inspection. “How about I give you this and you come back with me? I can give you other cold treats if you need something to alleviate the heat you are undoubtedly suffering from right now.”

When Megatron’s towering frame reached him, he sniffed the cube and huffed a bit. He took pity on him, though, as he started to eat it.

He munched on the cube, and when only crumbs of crystals remained on Optimus’s servo, he started to lick them up with his glossa. Optimus let him, as this is something Megatron loved to do, to not leave any crunched bit of energon on Optimus’s servo if he could. The habit of feeding Megatron by servo was one of the first signs of his trust as a traumatised little bull, and it has stuck over time.

Optimus frowned in confusion when Megatron’s glossa kept lapping at his plating even as the last bit of energon was devoured. He lifted his other servo to scratch behind Megatron’s ear, wanting to divert his attention. “Come on, Megatron. We should leave. If you do not wish to spend the season with the others, I can free a pen for you to spend it in peace.”

Megatron’s optic locked with his, a heated look coming over them. He suddenly transformed, his two pedes planted on the ground and his servos snaked their way around Optimus’s waist. Before Optimus could do anything, Megatron threw himself at the red and blue mech.

Optimus cried out as he was thrown to the ground with the full weight of the giant bull on top of him. He lay there in a daze, barely feeling it as Megatron nuzzled his faceplates. After regaining his bearings, he propped himself on his elbows and looked up at Megatron, fear and confusion warring inside his processor.

Megatron stared intently at him, his gaze devouring what it could as Optimus trembled underneath him.

Optimus searched Megatron’s faceplates, from the red optics gleaming down at him to the steam flowing out of his vents. Cold realisation descended on Optimus’s processor, and he started to struggle as he pleaded desperately, “Megatron, no! You shouldn’t—” He was cut off as Megatron’s intake slammed on his own, his long, ridged glossa slithering inside and silencing his voice.

Optimus struggled, his servos scrambled to find their grip on Megatron’s armour and push as hard as they could. He could feel Megatron’s glossa mapping the inside of his intake, the long appendage wrapped around his glossa and played with it.

Megatron’s dermas were unrelenting, refusing to let go of his intake. Optimus could hear his fans turning up as they tried to circulate air through his frame.

With one final tease at the far back of his intake, nearly to his cables, Megatron withdrew, watching proudly as Optimus coughed and sputtered to clear his pipes.

Optimus panted and tried to wheeze out words to calm Megatron and get him to stop this, “Mega–Megatron, you can’t do this! If you want a mate, I can still try to find ano—”

Megatron ignored him and trailed his servos down his frame, then cut him off as he pawed at Optimus’s modesty panels.

“No! This is wrong—Megatron!” Optimus jerked in fright, his struggles renewed, and he thrashed. Megatron was immovable, his weight far exceeding Optimus's.

Megatron gave him an annoyed stare for his flailing, palming Optimus’s modesty panelling more firmly as his digits closed around the seams, his sharp claws doing their job as they dug deeper. With a grunt, Megatron ripped Optimus’s panel away, exposing his array.

Optimus howled, the pain was unbearable to his sensitive protoform, and he could already feel energon leaking from where the panel was ripped out. Megatron stared at his valve for a moment, drinking in the plush blue lips highlighted by red biolights as his external node lay dormant for now.

The farmer mech sobbed as he felt Megatron’s glossa lick his energon away, almost in apology. Then his breath hitched as that glossa started to circle his array, targeting his valve rims. An involuntary moan broke out of his dermas as Megatron’s glossa brushed his external node.

Megatron looked up at the sound. He saw Optimus’s flushing faceplate, and he beamed, happy that despite his inexperience, he was already bringing his chosen mate pleasure.

He went back and started licking around that area ravenously, listening to Optimus’s sounds to guide him as he flicked his glossa on the node when it blinked red, then he wrapped his glossa around it and squeezed. Optimus cried loudly, his frame now jerking into Megatron’s touches, begging for more.

Optimus’s processor was boiling with pleasure and shame. He couldn’t believe he was getting off on this, that his charge would soar higher than it ever had, and it was at the servos of one of his mechanimals, not just that, but one he had practically raised since adolescence.

He wished for the ground to open up and swallow him whole. On the outside, however, he was moaning and crying wantonly, his servos came up to shield his optics in shame.

So caught up with the sensations raining on his node, he barely felt it as Megatron’s digits prodded his valve rims. His servos flew down to grab Megatron’s pauldrons desperately in a crushing grip, his expression pleading. “Please, don’t,” he whispered, sounding defeated with coolant threatening to stream down his faceplates.

Megatron paused and extracted himself from Optimus’s array. He gazed at his caretaker, wondering what would get him to accept his claim. He leaned and pecked Optimus, much to Optimus’s dismay and hitched sobs, and licked around his dermas. He trailed up to one of Optimus’s audial fins and ran his glossa up and down in what he believed to be a soothing gesture.

When Optimus’s grip on his pauldrons faltered and he groaned, the bull counted it as a win, and his digits went back to their prodding and stroking on the outer valve. Lubricant was leaking from inside, so he nudged a single digit in, careful of the sharp tip as it opened up the port.

Optimus whined, feeling the intrusion. He had not had berth partners before, and the odd sensation struck him as alien. He prayed to Primus that his seals wouldn’t be broken today, but it seems fate had other plans.

Megatron dug his digit deeper to spread the valve callipers, working tirelessly to lick and kiss Optimus’s helm and faceplates to distract him, then felt a barrier that stopped his digit. He poked at it and felt its elasticity.

He knelt further down, bringing his faceplates in front of Optimus’s entrance. His digit was still inside, and he tested the callipers by moving it around. Satisfied with the stretch, Megatron worked another digit into the valve.

Optimus gasped and squirmed, the stretch starting to burn. He bit his lower derma as the bull sucked his external node, the graze of denta on it cranking his charge higher than it has a right to.

Soon, Megatron inserted another digit, thrusting it back and forth, each time hitting that barrier inside. He spread his digits as wide as the port would allow, uncovering strips of biolights that bathed him in different colours.

Optimus blinked in confusion as Megatron emitted a deep bellow. Despite the strain of the stretch, he looked down to see Megatron inspecting the inside of his valve with a hungry look. Mortification soon took over, and Optimus threw his servos down to grip Megatron’s horns in an attempt to push him back.

Megatron’s trance was broken when his helm was yanked away. He looked up angrily, meeting Optimus’s optics, humiliation and exertion colouring his faceplates into bright energon hues. The sight struck something within the bull, and he kept his hard stare at Optimus as he dipped to lick around the entrance before plunging his glossa inside.

Optimus threw his helm back with a cry, feeling the ridges on Megatron’s glossa brush all the sensory nodes around them. His grip on Megatron’s horns tightened, and he unconsciously ground Megatron’s faceplates on his array using it.

Megatron was thrilled that his mate was finally being proactive. He doubled his efforts by eating Optimus’s valve out and drinking the globes of lubricant that gushed from its depths. His glossa kept pumping into the seal, and after a while, he got frustrated. He needed to break the barrier that kept him from the rest of Optimus’s port. Megatron let Optimus grind into his intake for a moment, then he extracted himself. Optimus’s servos slackened their hold on his horns before falling away as Megatron rose to meet him.

There was the sound of partial transformation from below, and when Optimus looked down, he was met with the terrifying sight of a bull’s spike fully pressurised and popping against his abdominal plating. Not just any bull’s spike, as Megatron far exceeded the size of his peers, and that reflected in his interface equipment. Optimus had seen it before, as he had personally done maintenance for Megatron ever since he came to be under his care. Even then, seeing it up close when Megatron was in his rut was frightening. The spike gleamed silver with red biolights, the ridges flared out near the tapered tip, with the sides lined with pumps.

The realisation that Megatron wanted to frag him with this girth hit Optimus, and he clawed at the ground to scramble away. Megatron crushed him down with his weight, keeping him in place. Optimus cried in terror as Megatron nudged the tip of his spike against his port, his vocaliser glitching as he pleaded yet again, hoping that Megatron would regain his senses, “you can’t! It won’t fit—Megatron, stop, stop! Please!”

Megatron grunted, securing his grip around Optimus’s hips to keep him still, then looked down to observe his work, working the head of his spike inside after a few misses. Once the tip caught on to the port, he grinned in victory and started to push it in as slowly as he could, groaning loudly when he felt the mesh of the walls around him envelop his spikehead.

Optimus muffled his screams by biting his servo, the other one latched onto Megatron’s pauldron in a creaking grip and tried to push him away. The feeling of the huge girth slowly making its way inside, spreading his callipers to full capacity, was maddening.

Before long, Megatron’s spike finally reached the seal, and he stopped to vent a bit to expel the heat. His spike felt in heaven, the plush walls around it messaging and tightening in equal measures. He straightened up, lifting Optimus’s hips a bit and then slamming down, breaking the seal in one go.

This time, Optimus’s shouts could not be muffled, and his vocaliser fritzed as its output kept being re-evaluated by different neural sensors, lost between overwhelming pain and pleasure. Megatron let him scream himself hoarse as he started thrusting roughly into the valve, having only gotten half of his spike in and wanting more of the pleasure that clung to his processor as he kept working another ridge in. Energon and lubricant were mixed as they leaked from the port.

By the time Megatron finally reached Optimus’s forge, the mech was sprawled on the ground, panting and groaning in rhythm with Megatron’s thrusts, his pedes spread as far as the joints would allow. He jolted when he felt Megatron’s spikehead slam against his forge opening, the secondary seal protecting it for the moment. His weak voice box attempted to sputter out words through his sobs to deter Megatron. They were ignored as the silver bull drew back until only his spikehead was inside the port, then slammed back inside with all his strength, his spikehead broke through the seal and pierced the forge. Megatron bellowed loudly as he finally bottomed out inside the valve.

Optimus couldn’t scream for the pain he was in, he felt more energon and lubricant gushing out of his valve as Megatron started fragging him in earnest. Each thrust burned a fire under every last one of his internal nodes as the spike spread him open beyond his limits, his abdominal plating already denting with the pounding he was receiving. Every time Megatron thrusted in, he would make sure to break through his forge opening, his tip jabbing the oversensitive nodes on the walls of the forge.

Megatron panted with exertion, his hydraulics working overtime to send his spike inside that glorious valve over and over. He watched Optimus as he moaned in return, the mech’s processor delirious with the sensations assaulting his frame. His intake was open as all sorts of delicious sounds escaped his dermas. Megatron captured them in a deep kiss, wanting to possess Optimus fully.

His glossa resumed its earlier dance with Optimus’s, playing with it as he swallowed the sounds before they escaped Optimus’s dermas. He then moved his glossa deeper to thrust into Optimus’s intake as far as it would go, the tip brushing the inner walls of his mate’s pipes. He found a rhythm between his spike and glossa, thrusting them alternatingly into Optimus’s ports. Megatron looked in delight as that seemed to awaken Optimus, and he started to squirm and thrash against his hold again. His vocaliser strangled a cry against his intake, and he watched as Optimus seized and trembled again, the walls of his valve weakly attempting to tighten around him as overload hit Optimus’s systems.

Megatron grunted, Optimus’s overloaded charge licking against his frame. His own charge soaring in return, he abandoned all care and started chasing his finish. Optimus stirred against him as he felt a swelling in the smouldering spike that broke open his valve. The valve could do nothing as Megatron ground against the sensors inside, post-overload oversensitivity cranking up the wild sensations, making Optimus jerk against him and cry in painful pleasure.

The swelling centred on the base of Megatron’s spike, and Optimus’s slow-working processor barely registered the meaning of that before Megatron started to work it inside. Once his processor recognised what it was, he started to shake his helm in denial, searching Megatron’s optics for mercy.

Megatron ignored the pleading optics, focusing on thrusting as hard as he could. The pump forming at the base of his spike finally broke through the valve entrance, settling inside as Megatron finally reached his overload with a loud, drawn-out bellow. Hot transfluid splashed the walls of Optimus’s forge and rushed to fill his valve, the spike knot at the opening preventing any fluid from leaking out.

Optimus’s intake opened in a silent scream, his vocalizer no longer functional to give voice to his processing output. He could feel his valve callipers snapping and mesh tearing as everything from his valve lips to his forge stretched far past their maximum capacity around the monstrous spike that now rested contentedly inside him. Tranafluid filled him up so thoroughly, it could not slosh around and instead rested as a solid weight inside him because of the knot plugging him up. His abdominal plating bulged obscenely, denting his armour out of shape. He feared any slight move would crack his armour completely.

The bull was lost in the afterglow of overload, coming to the sight of his mate frozen in place, optics and intakes opened wide in horror. He gathered his mate up, shushing him as he stroked his helm and held it to the crook of his intake pipes, nestled safely between his pauldrons.

The slight movement jostled the knot at Optimus’s entrance, making his servos shoot out to hold on to Megatron desperately, his pedes wrapping around his waist as well. He buried his helm tighter against Megatron, not wanting any movement to graze his oversensitive valve, yet not wanting the knot to break his entrance further by sliding out.

Megatron huffed, wrapping his servos around Optimus in turn. Seeing how tightly his mate has latched on to him, he decided to stand up while holding Optimus against him. He moved to the giant tree he was resting under before Optimus’s arrival. Each step jostled his knot and spike inside the valve, making Optimus flinch.

He reached the tree and leaned his backstruts to it as he slid down until he was sitting with Optimus in his lap. He hummed and nuzzled what he could of Optimus’s helm, feeling the quivers of his frame. Slowly, he pinched Optimus’s chin and brought his faceplates up, frowning when he saw it wet with more lubricant trailing from his optics. He leaned down, and Optimus flinched, so he settled for chaste pecks on his dermas and forehelm to calm him down as his servo drew circles on Optimus’s backstruts.

Megatron stayed like this, waiting for his knot to deflate and spike to depressurise. He did not know how mechs' mechabiology differed from theirs, but he hoped that Optimus would take. The thought of having the beautiful red and blue mech heavy with his sparklings aroused him immensely, and more transfluid spurted out of his spike at the imagery.

On the other side, Optimus was miserable. His frame was close to bursting from the fluids within. The thought of interfacing with one of his mechanimals disgusted him. That emotion was not targeted at Megatron, the bull clearly was not in the right state of processor during the season, but at himself. How could he participate in this debauchery, to derive pleasure from it. Even now, with his valve growing numb to the pain of the stretch, his nodes were sending weak signals of pleasure to his neural net. Megatron was barely an adult bull, despite his impressive physical stature. He spent more time around Optimus than his own fellow bulls and cows, which must have highlighted his solitary nature.

Optimus wished his voice box were not overclocked, so he could apologise to Megatron for the life he had robbed from him. He could only hope that he could fix this after the season ended and Megatron regained his higher function processing. For now, he could only quiver in silent tears and caress Megatron’s backplates in what he hoped to be perceived as an apology.

The pressure in his valve slowly eased with time as the knot plugging his port dwindled. Megatron grunted as the knot came loose enough that fluids leaked, then splashed on their lower frames. He eased Optimus’s hold on himself enough so they both could see the mess down there.

Megatron rumbled lowly as he saw how Optimus’s valve stretched around what was left of his knot. Transfluid, lubricant and energon spurted from their connection, painting their abdominal platings and thighs in the mixed colours before pooling on the ground below them.

The bull grabbed hold of Optimus’s thighs, slowly lifting his slighter frame off his spike. Optimus’s vents hitched as the barely-there knot nudged its way out of his entrance. His valve lips have long given up on closing, and that left his valve gaping open and streaming fluids as the spike left it.

Mrgatron’s spike was depressurised but still hung in the open as Megatron made no move to retract it to its housing. Optimus could barely bring himself to look at the girth that rearranged his insides. The traces of their interface were going to be hard to remove, as Optimus’s abdominals still bulged as though he were carrying. The sight excited Megatron again.

The farmer mech tried to in-vent deeply and get his systems sorted. He focused his primary tasks on getting his voice box functional for now, wanting to vocally placate Megatron so they could return to the farm and fix this. He didn’t want Bumblebee to come investigating where they disappeared to and see this depravity.

Optimus’s train of thought was cut off when Megatron turned his frame around. With a secure hold on his exhaust pipes, Megatron lowered Optimus to the ground onto his front on servos and knees. Optimus squirmed and flailed in confusion, then was cut off by the sounds of transformation behind him.

He froze, then looked over his pauldron in fear to be met with the sight of Megatron in his full quadrupedal bull mode looming over him. The bull’s now fully pressurised spike caught his optics, and he immediately tried to scramble away. Before he could get away, one of Megatron’s hooves slammed his backstruts, planting his upper chassis to the ground. Optimus wheezed what would have been a shout. His aft was high in the air as Megatron’s lower limbs lay folded upon his pedes, keeping the rest of his frame in place.

Optimus shook his helm, tears blooming in his optics yet again, coating his visual feed in a film of coolant. He tried to rasp the words, “no, please, Megatron, please don't—” to no avail. He looked back, seeing Megatron lower himself to clink their helms together. The bull buffed hot vents into Optimus’s faceplates, indicating that the heat in his frame persisted despite their earlier coupling.

Megatron nudged his spike against Optimus’s array, finding difficulty in breaching him without his servos to guide the cord. Optimus knew it to be useless with how his frame was nailed to the ground, but he squirmed to deter Megatron’s progress.

The bull’s spike finally caught on the gaping valve, pushing the spikehead in before he slammed the rest of the way inside. Optimus’s visual feed glitched from the impact, the unbearable weight settling inside him again so soon. His forge was pliant and did not resist the spike’s intrusion anymore.

Megatron threw his helm back and bellowed the loudest he had yet. His mate’s valve wrapped its wet walls around him lovingly, the callipers inside broken wide too far to squeeze him out. He started thrusting roughly, this form spurring him to accelerate his speed.

Optimus could do nothing but accept his fate at this point. His helm thunked to the ground as he all but lost sensation to the rest of his frame, except for the burning whirlwind of sensations inside his valve as Megatron bounded into him. The pumps along the spike dragged along his inner nodes to create lasting pleasure. Oral fluid leaked from his gaping intake as his optics stared into the distance without seeing anything.

Megatron watched his mate as he fully submitted to him, his frame angling up to receive his thrusts better. He leaned his helm and licked his faceplates, drinking in his optic coolant and oral fluid. His glossa snuck into the open intake, prodding inside. His charge was rising with the speed of his thrusts, making him grind roughly into the forge walls with every plunge. The start of another knot made itself apparent as his thrusts started to face resistance at the entrance.

Optimus’s glossa started to move with Megatron’s, making the bull overjoyed as his mate sluggishly reciprocated his touches. His optics were still glitched and glazed over as his charge took control of his limbs. Optimus went rigid and his valve squirted lubricant in his overload, his processor offlined temporarily.

Megatron followed him closely as his knot fully formed at the entrance, half of it still outside, making him have to squeeze it the rest of the way in. He huffed and panted, his vents slowly evened, and his spike kept pulsing, pouring more transfluid into the valve with each pulse.

Having finally completed the claim, the bull felt content and exhausted. He nuzzled against his mate’s faceplates happily.
Megatron waited until Optimus came online again before shifting a bit, lying fully on the ground with Optimus’s frame nestled against his, making sure not to crush him with his full weight as he settled down. His spike and knot were still nestled inside his mate’s valve as his systems started his recharge protocols.

Optimus’s processor was chaotic, his voice box inoperational, and his visual feed filled with static. He could do little but lie there and let Megatron snuggle up to him, the bull enveloping Optimus’s frame with his own. His valve throbbed with the content filling it up, warnings of overcapacity pinging his systems.

The last thing Optimus felt before his systems powered down was Megatron’s limbs encircling his frame, the hum of his engines lulling Optimus to recharge.