Megatron smiled at the sight in front of him, his spark whirling eagerly in his chest as he took in the sight of his archenemy's massive frame sprawled out on the berth in the center of the room. Optimus Prime lay back, his head tilted toward the door as he watched Megatron enter, his limbs sprawled out over the berth in a posture clearly intended to look enticing.

He'd been expertly repaired and freshly painted, the red surface of his chest plates glittering as the cool light of the room played over it. And his shoulders, so long marked with the hated symbol of Megatron's enemies, each bore a mark he'd left.

One was a scar. The two mechs had fought, and Megatron's Dark Star Saber had torn through the plating of Optimus's shoulder, scoring a jagged line through the Autobot symbol. Megatron had forged the blade out of a chunk of dark energon, and the corrupted substance had eaten through the metal, leaving no trace of the insignia. Despite the medic's exacting attentions, the shoulder still bore a livid black mark. Medical treatment had stopped the advance of the corrosion, but the scar would never fully heal.

But as much as Megatron liked seeing the scar, the newest mark pleased him even more, sending a warm crackle of heat through his circuitry and making his cooling fans roar. That was his own insignia, freshly welded on Optimus's left shoulder, gleaming silver in the light.

He'd seen that mark there once before. Then, it had been a mark of allegiance, though that fealty hadn't lasted nearly long enough. For a few brief months, the Matrix of Leadership had been lost, and Optimus had reverted to the mech he'd been before the war, the protégé Megatron had treasured. But the Matrix had been restored, and Optimus had lost the memory of his time among the Decepticons.

And his time in Megatron's berth.

But now, he wore that mark again. Megatron's claws curled possessively as he looked at it. Now it was a mark of ownership. A sign of possession.

The wall behind the berth echoed it, an enormous version of the symbol inlaid into the metal. Optimus was looking at Megatron now, carefully propping himself up on one arm. Megatron smiled in cruel amusement. Holding that pose would have to sting. And the sting would only further remind Optimus of his place here.

"Hello, old friend," Megatron said, his voice a dark purr.

"Megatron," Optimus answered. The optics he fixed on his new master were hardly the optics of a willing berthmate, or even of a pleasure drone. They gleamed a cold, flat blue, and the brow ridges over them slanted down sharply. A battlemask covered Optimus's mouth, making him look more ready for a fight than for a coupling.

Energy thrummed through Megatron's frame, but Megatron had removed the arm that held his weapon. He'd had to do it. Forging the Dark Star Saber had required stealing the arm of a true Prime and grafting it onto his own frame. Without the new arm, he could never have wielded the sacred Forge that he had used to shape the blade.

Losing his cannon was a worthwhile sacrifice. His weapon had been powerful, built for him by one of the most brilliant scientists on Cybertron. But with the Forge of Solus Prime, Megatron had crafted Dark Star Saber from the crystallized blood of Unicron himself.

Still, giving up his own right arm meant his frame had no built-in weaponry. He hadn't grown used to that, and doubted that he ever would. His systems crackled with energy, seeking to feed it into weapons systems that his frame no longer bore. Unable to go anywhere, it spread through his circuits, an intense, crackling heat that pooled in his interface array.

But Optimus's optics still shone with the cold light of a soldier. The Decepticons' medic had disabled the transformation protocols that would enable him to transform his hands into weapons, but he was no less dangerous for that.

And the blade slung over Megatron's back was a weapon of last resort.

"Easy, Optimus," the warlord hissed, stepping closer to the berth. "There is no need for such hostility. Not any more."

Optimus watched him. The bright blue optics narrowed.

"The Autobots have left. They are no doubt in the far reaches of the galaxy by now," Megatron went on, his voice lulling. "No harm will come to them."

Optimus's engines revved in a growl.

"I have what I want," Megatron said flatly, snarling in irritation. "As long as you are here and they are gone, I have no reason to pursue them. And no reason to lie to you."

"Then you intend to keep your word."

"I do."

Years ago, Megatron might have said more. He might have raged at his friend's suspicion. Now he had nothing more to say. Now his words would be enough or they would not. Optimus would believe him or he wouldn't, and he had nothing left to offer either way.

Optimus cycled air heavily through his intakes. Then he nodded.

Megatron smiled. "Take off your mask."

The twin plates of metal covering the lower half of Optimus's face slid aside. Megatron stared greedily at the smooth, silver surface of the cheek plates and chin beneath. The battlemask had been carefully polished, but hints of age remained, faint scratches and scars that testified to centuries of war. Optimus's face was pristine, and gleamed.

The silver mouthplates were locked tight in a grim line, betraying no emotion.

You agreed to come with me when I spoke of love, Megatron thought. Have you forgotten that so soon already, my old friend and enemy?

Or is it your own emotions you resist?

Megatron leaned in, wrapping one arm - his real arm, the one he'd been built with, the one tipped with pointed, silver claws - around Optimus's massive back. He felt Optimus shudder and gripped tighter, pressing his scarred mouthplates to the smooth silver of his mouth.

Optimus cycled another heavy sigh. Then, all at once, his mouth opened wide. The plating under Megatron's hand relaxed, perhaps in despair and perhaps in surrender.

Megatron pressed eagerly against him, his fangs worrying the pristine mouth. His cooling fans roared, and he heard the low, growling echo as Optimus's own fans kicked on in response. The plating under his hand warmed, and he wrapped his stolen arm, the arm of another Prime, around Optimus's back.

"Megatron -" Optimus moaned against Megatron's mouth. A plea for more? A protestation? Megatron couldn't tell.

But Optimus belonged to him now. The deal had been made. The mark of his possession gleamed on the former Autobot's shoulder, and with the rest of Team Prime banished to deep space, no one would ever gainsay his ownership again.

Megatron's claws skirred over Optimus's back, scraping lightly at transformation seams. The blunt fingers of the stolen Prime's arm slid between gaps in the plating, making Optimus's azure optics narrow and flicker.

Then Megatron slowly slid his fingers free. "Lie down."

Optimus's engines revved again, but he made no protest, settling down on the berth and gazing up at his new lord, his expression unreadable.

For a long moment, Megatron did nothing, cycling air raggedly as he stared down at his prize.

"They made you beautiful," he murmured.

He knew very well what Optimus's frame looked like. The broad chest adorned with glass, thick-plated arms and legs, and dark hands that transformed as easily into blades as into blasters had been seared into his memory from the moment the Autobots' new leader had taken the Matrix into his chest. From the moment the small, unremarkable frame of a young mech of the scholarly caste had shifted before his optics into a massive, living weapon.

But that upgrade had been a betrayal, and the thing it had created had become his worst enemy, and he'd had nothing but hatred for the thick armor that had hidden away his wisest advisor, the circuitry that had spread betrayal and poison through the mech that had once been his closest friend.

And that he had wanted from the very beginning.

But now, that hated frame lay before him in surrender. Now, he saw not the mockery of a warrior, transmuted for no purpose but his destruction, but the broad frame of a skilled soldier and wise strategist. The frame not of a mockery, but of a mech who had been honored.

His spark whirling with something he could not name, he reached out to touch Optimus's side, the blunt fingers of a long-dead Prime tracing slowly over the metal of the last one living.

Optimus shuddered at the touch, fists clenching. He cycled air through his vents in a ragged pant.

"Old friend -" Megatron rasped, the syllables torn from some old, buried part of him, the words twisted by the memories of a long-ago betrayal.

Megatron reached out with his other arm, the tips of his claw sliding down Optimus's side again, stopping briefly at the Autobot's hip and curling over his pelvic plating. Optimus's cooling fans whirred again, a low, soft sound. The already slitted optics flickered.

Megatron lowered his head, pressing his lip plates to the cabling of his former enemy's neck. He rubbed his scarred mouth against Optimus's neck with a rumbling purr.

His hand slid over to Optimus's interface array, the pointed claws tipping his fingers circling the cover of Optimus's spike and then moving slowly downward to do the same to the cover of his partner's valve.

Lubricant leaked from the seam, a smear of bright quicksilver staining the plating. The tip of one pointed claw moved to touch the beaded liquid.

Optimus froze, cycling air raggedly through his vents, his optics flickering in indecision. His vocalizer gave a low, monotone hum and he lowered his hands to the berth, forcing his frame to relax. "I gave you my word that I would not resist you."

Megatron growled deep in his chassis. "Is that all this is about, then? Your word?"

Cycling another heavy sigh, Optimus retracted both covers. More lubricant, silver and shimmering dripped from the open valve. Above it laid Optimus's spike, half-pressurized, the silver metal ringed with blue.

Megatron grinned. So you do still harbor some desire for me.

"I did this for the others' sake." Optimus's voice was stern. "You know that."

"For the others' sake," Megatron repeated, still staring eagerly at the twin prizes Optimus uncovered before him. "Not for your own?"

"This is coercion, Megatron," Optimus ground out. "I paid for the Autobots' freedom with my own." The broad frame twitched, and Megatron saw a bead of moisture glitter at the tip of Optimus's straining spike.

Megatron's lip plates curled in a sharp smile as he reached down to wrap a claw around it. "This is what we both want. What we both have always wanted."

He began to move, slowly and carefully, the tips of his claws a ring of blades circling his prize. Optimus shuddered again, his optics narrowing. Then he groaned, a low sound from deep within his chassis, his mouth opening wide.

Megatron's grin widened. His own spike, pressurizing rapidly at the sight, thudded against its cover, impatient to be freed. I knew you would give in, old friend.

"Do you remember this, Optimus Prime?" he whispered, his voice gravelly and soft. "Do you remember my hands on you? My mouth?"

"I saw the recording." Optimus answered, his voice laced with static, his optics bright slits of blue. His hips jerked, pushing his spike into Megatron's hand in spite of themselves. "But - the Matrix was gone. I - remember nothing."

"The Matrix," Megatron spat, his fangs gleaming as his mouthplates drew back in a grimace. "It turned you against me once, offering you power I could not."

"The Matrix is a sacred trust, Megatron. It -"

"It stole your memories of me." The clawed hand moved faster over Optimus's spike, gentleness giving way to force. Optimus twisted in Megatron's grasp, wincing, fighting his hips' instinct to move.

Energy crackled through Megatron's systems again, the trapped heat that might have fueled his weapon. He clutched tight at the spike gripped in his hand, so hard that Optimus winced.

Then the former Autobot mewled, a choked, needy sound. It was not the sound a Prime would make. It was a sound Megatron had heard before, in that brief period when his old protégé had come to him, the memories of their long war temporarily erased.

Megatron loosened his grip, opening his hand, tracing the tips of his claws over the sensitized metal. He moved slowly, his touch light. One small mistake and the blades tipping his fingers would pierce the thin plating.

And while he might have made another Decepticon bleed that way and savored the experience, Optimus would never understand that.

"It stole your memories of us," Megatron whispered, listening to the stutter of Optimus's cooling fans as he relaxed into the warlord's hand.

Optimus paused a long moment, forcing himself to be still as the sharp claws danced over his spike. Then he spoke.

"I do not regret the choice I made, Megatron. I - I had no other choice. But - I regret this rift between us."

Megatron's optics flared with anger. Then he shook his head bitterly and smiled, his optics dimming. He lifted his hand, moving his claw off of Optimus's spike. "Then let us repair it, old friend, in the only way left to us."

Cycling air heavily through his intakes, the warlord slid his own cover aside. His spike sprang free, the thick bludgeon of a gladiator, plain, unadorned silver. He gasped, feeling the air hit it.

Optimus nodded slowly, canting his hips to better present his valve and opening his legs wide.

Megatron's spike twitched and his spark contracted, heavy with heat, but he did not move to pull Optimus closer, or lower himself down to line up his spike with the waiting valve tilted toward him. Instead he bent down, lowering his head to the valve's rim.

He and Orion had done many things during Orion's short stay with the Decepticons; this had been one. But Megatron had not recorded it, and Optimus had forgotten everything once the Matrix had been reinstalled. He would not remember this.

Megatron opened his fanged mouth, pressing the sharp denta to the rim of the valve just as he'd touched Optimus's spike earlier. Optimus shuddered, fighting to be still.

Megatron's frame vibrated, a humming purr, half pleasure of his own and half reward. He wrapped his mismatched hands around Optimus's hips, holding him still.

So a part of you still does belong to me, he thought, pleased enough to draw his fangs away and extend his glossa to lick at the rim of the valve.

It should have been no different from any other mech. Orion Pax had been built in Iacon, far from the factories of Kaon or the Badlands where Megatron and most of his followers came from. But parts were parts, and fuel was fuel, and even if a mech from Iacon had once lived on finer fuel than a mech from Kaon, it should not have changed the way anything but an energon leak might smell or taste.

And centuries of war and exile meant that Autobots and Decepticons alike, leaders and their followers, all drank the same, simplified fuel anyway.

And yet, the taste of the lubricant as Megatron slid his glossa inside the valve he'd claimed and lost and the electrical charge sparking over the sensors as his glossa moved over them set his processor reeling. He thought of Iacon, the one time he'd made the journey to see the young mech who spoke to him with such awe and eagerness. He remembered the domes of the city, polished and pristine, gleaming more brightly than anything Megatron had ever seen - or would see since, once the planet itself fell to war. He remembered light, light everywhere, undimmed by the smoke and smog of the Badlands. The optics of a young scholar, bright as those lights, searing his own optics when he looked too deeply into them.

His own frame shuddered, heat lancing through his systems, as he felt the Prime's hand wrap around the back of his helmet, tentative at first, then locking around the metal with a grip as forceful as his own - the grip of a warrior pulled from legend, blessed by powers beyond his ken.

Is it the Matrix that makes you taste like home, Optimus Prime? Megatron thought, his spark twisting with poison-sweet bitterness as he laved at a sensor node at the top of the rim of the valve, feeling the tang of charge crackle like lightning over his glossa and lip plates.

His hands locked tighter over the hips they held, surprisingly narrow for such a broad frame. Optimus made another gasping sound, torn from somewhere deep within him, somewhere beyond the Matrix, beyond war, beyond everything but the present, the touch he had craved for so many centuries - and then forgotten.

He ground his hips hard over Megatron's scarred mouthplates, heedless of anything else, and overloaded, his engines turning over with a rumbling roar, his vocalizer emitting a small, quiet gasp, as though too awed for anything more.

Megatron pressed his lip plates to the rim of Optimus's valve for as long as he dared, the energy of his partner's overload still moving like little jolts of lightning over his plating. Heat pooled in his interface array, and his spike had pressurized so much it felt almost like pain.

Slowly, as though he'd just awoken from some particularly vivid dream, he rose to his full height, his spark crackling with unspent energy, his circuitry a golden latticework of heat.

Optimus lifted his head, his optics flickering as his systems reset. Then they widened.

"Megatron -?"

Megatron grabbed Optimus's legs, pulling the big mech toward him as effortlessly as he might have dragged the small frame of the scholarly mech Optimus had once been. He saw Optimus sit up, the dark mark on one shoulder and the silver of his own mark winking at him from the other.

His frame rumbling in a growling purr, he reached to press his spike against the entrance to Optimus's valve. A gush of new lubricant poured from it, smearing his spike, and he shuddered as a wave of bright heat coursed through his systems in response, so intense his optics flickered.

The only answer he had to offer was to drive into the waiting valve, the heat around his spike matching his own.

Orion Pax had been built a scholar, his frame far smaller than Megatron's. Megatron had spent nights imagining the tightness of the younger mech's valve, gripping him impossibly tight. Starscream had been as small, and he'd relished the way it felt to batter his way in, the walls of the valve tight around him, some denting as his spike blasted its way inside.

He'd imagined that Orion would be the same - after enough coaxing to encourage him to try it, eagerness and desire driving him to do something he would have feared. But war had come before he'd ever had the chance to claim his protégé that way.

And Optimus was different, his frame almost as massive as Megatron's own, the valve perfectly sized to fit him. His spike was still big, and feeling Optimus buck back against him, he knew it must be wide enough to hit most of the sensors in its walls. But this felt good, felt right, the bruising force he'd used so many times to bring Starscream to heel was neither wanted nor required.

His hands clutched tight around his partner's hips as he drove in hard. There was no need for force but there was no need for deliberation either, not here, not at the end of all things. He thrust as quickly as his frame would allow, the friction driving him on, the charge building over his spike impossibly intense, a terrible pleasure as consuming and intense as pain. Static fuzzed in front of his optics again and he heard Optimus cry out, his audio receptors ringing with the sound. He did not know if it was the thunderous cry of a titan or the high gasp of a youth rediscovered and relived, and his spark pulsed hard and hot in his chest as he realized he no longer cared either way.

He felt Optimus tilt his hips, the walls of the valve shifting to admit him even more fully. He remembered the fit from the brief time they'd spent together before, when the Matrix had been depleted and nothing had remained to stand in his way. But he didn't remember this, the frame of his closest friend turned greatest enemy turned whatever he'd become, opening in such surrender.

What will happen now? he wondered, the hands gripping Optimus's hips twitching, tensing so hard he felt beads of warm energon where his claws had pierced the plating and a dent where his stolen hand had dug in hard. Will you curse me when this is over? Or will you come to me willingly after this - my love?

He drew back as far as he could stand and then drove in, crying out half in triumph and half in desperate, naked need as his spark pulsed, energy bursting from it in a nova of heat and light as the fluid burst from his spike in the same moment.

As his vision went white, he heard a voice, beloved and familiar, calling out his name.