Title: Fireflies
Rating R for plug'n'play
Characters/Pairing: Knock Out/Breakdown
Summary: Ah, the mating habits of ground-based vehicles!

Cybertronian programming was complicated. It was made up of countless lines of code dictating and influencing behaviours, functions, and ways of thinking that had been revised, added to, deleted, and recombined over a span of millions of years. An almost endless series of programs, all interacting with each other; activating, deactivating, altering, masking, rearranging, multitasking. A programmer could spend a lifetime trying to tease apart the mysteries of Cybertronian programming, mapping the cause and effect of each piece of code, and barely solve a fraction of it. The end result of all this chaotic digital evolution was the occasional stray program that no one remembered where it came from or why it was there to begin with, but couldn't quite pinpoint and remove without the loss of other functions.

One of these stray 'instinctual' programs was why, every few stellar cycles, Breakdown found himself irresistibly attracted to car headlights.

After so many years alone with Knock Out, Breakdown's bizarre cycle had slipped his mind, so when he caught some of the car-based Vehicons drag racing on the Nemesis the swell of desire took him by surprise and hit like a semi full of lead bricks. His mouth dropping open, Breakdown jolted to a halt mid-step as the light of so many sets of headlights washed over him. Almost immediately his cooling systems kicked into high gear as his processors went into overdrive with the activation of multiple resource-intensive programs. One of the programs sent a tingling sensation shooting straight down his back and into his interface cables, making them squirm beneath their protective panels.

"Guh," Breakdown managed to choke out as the wave of arousal shuddered through his massive frame.

Several of the spectating Vehicons standing nearby turned to look at him, their immobile faceplates as unreadable as Soundwave's. They shared glances and shrugs amongst themselves before one drone stepped forward slightly and asked, "Breakdown, sir? Is something wrong?"

"Uh, nh," Breakdown replied as he straightened, his optics fixated on the bright headlights of the racing Vehicons. He didn't have a lot of processor-power to spare at the moment, with one of the ancient programs busy duplicating all of his cognitive programming. He shook his head in an attempt to regain his focus and tried answering again in his usual dry tone, only just managing to keep a tremor out of his voice. "Does Starscream approve of you wasting fuel in your spare time?"

The crowd of Vehicons shifted nervously, and one of them spoke, "It... it's training?" The others nodded in agreement and muttered their support.

Breakdown gave a half-hearted chuckle, not actually bothered by what drones did in their spare time. He wasn't going to be the one to bring Starscream down on their heads. Their lord could look after his own troops. Not that Breakdown wasn't taking a good look at the troops himself right now. Yellow optics flicked from vehicle-to-vehicle, ages-old programming homing in on the brightest set of lights.

There! That one! Another surge of arousal lanced through Breakdown as he picked his target, stalking forward as his chosen Vehicon screeched to a halt, race won, and transformed. The Vehicon jolted in surprise to suddenly find Breakdown looming over him, staring down at him with an intimidating intensity. The Vehicon froze, wondering what he'd done wrong, if he was going to meet the same fate as many drones did at the hands of higher ranked Decepticons, if maybe he should try running…

Then Breakdown cocked his hips to one side, bracing a hand against them, and smirked down at the brightest Vehicon with half-lidded optics. "So, uh, you wanna go get some energon or something?"

Breakdown's cooling systems were humming audibly now, having reached a particular pitch that was intended to trigger a complementary set of ancient programming in those around him, driving them wild. Unfortunately for him, drone programming was stripped to the basics, leaving them with only a limited capacity for learning, thinking, and developing individual personalities, as well as freeing them from most vestigial coding. Without any complementary programming to activate, Breakdown was left with only a very confused Vehicon.

"I already had my energon ration for this solar cycle," the Vehicon said nervously, trying to slowly back away from the imposing Decepticon.

Breakdown followed after him, pressing further into the drone's personal space. His every circuit was humming for the Vehicon. He wanted him, needed him, wasn't sure he could take no for an answer-

A blaze of high beams from behind him threw the world into stark contrast and a smooth, familiar voice filled his audio-receptors. "Breakdown, what do you think you're doing?"

Breakdown turned, distracted by the new light, and had to squint against the brightness that was Knock Out's headlights, far outshining anything the drones had to offer. Taking the opening, the Vehicon Breakdown had taken an interest in made a quick escape, fading into the crowd of identical Transformers.

Knock Out stalked toward his partner, optics narrowed predatorily, while Breakdown's own gaze fixated on his swaying headlights. The humming of Breakdown's systems filled his head as he approached, sending curls of pleasure out across his sensory net as his own vestigial programming booted up. Instinctive possessiveness welled in his chest and he shot glares at the Vehicons gathering to either side, flashing his bright lights pointedly. To anyone with the right programming it was a challenge and an assertion of his dominance over dimmer cars, proving that only he deserved Breakdown's attention. To the Vehicons it was simply confusing and they watched, mystified, as Knock Out flashed them one last time before grabbing a hold of an enamoured Breakdown and dragging him off.

The pair didn't get far. At the first out-of-the-way alcove they encountered, Knock Out shoved Breakdown roughly against the wall and pinned him to it with his own body. The vibrations from Breakdown's cooling systems pulsed through him from every point of contact and Knock Out hummed with pleasure. His own cooling systems purred to life, shifting pitch until they synchronized with his partner's and the sensations resonated deliciously between them.

"Naughty, naughty, Breakdown," Knock Out said, trailing his hands up his partner's thick thighs to grip his hips. Sharp fingertips dug into metal, drawing a shudder and a moan from Breakdown and leaving scratches in his paint. Knock Out wouldn't abide by such rough treatment of his own finish, but he absolutely loved leaving his mark on others. Mine. "Looking at drones like that, when you know you belong to me."

"Uh," Breakdown gasped as Knock Out's hands trailed up his sides, teasing seams and dipping between panels. It was so hard for him to think. The vibrations felt so good. Knock Out felt so good. All the necessary programs were primed and ready and his head felt like it was full of fire. A fire that only one thing, one person, could put out. He fumbled desperately at the panels covering Knock Out's interface cables only to have his hands slapped away. He whimpered with need, his superior size and strength forgotten in the face of Knock Out's dominance and ages-old programming. "I- I need you."

Smirking, Knock Out pressed his lips to Breakdown's chest. He loved it when his assistant was like this, however rarely it happened. Already so delightfully wanton with so little stimulation. And he loved what the heavy 'Con woke within him, too – the dark, possessive burn that made him want to take and dominate with such primitive abandon and destroy any obstacles that came between him and what was his.

"That's right," Knock Out said, voice dripping like honey, "You need me."

He released his interface cables, the semi-prehensile cords uncoiling from beneath his shoulder plating to twist around his partner. One of them snaked its way up Breakdown's arm to tease his lips and he took it in, obedient as ever, and sucked, drawing a long moan from Knock Out. The sound was like music to Breakdown's audio receptors and as pleasurable as any caress.

At the insistent prodding of Knock Out's fingers, Breakdown released his own interface cables and relinquished his hold on the connector in his mouth. The cables twined together, writhing, seeking, testing, and when each found its partner they slammed home. Output to input, input to output. System to system.

Firewalls dropped.

In unison, they cried out in pleasure and arched into each other, grasping and clutching and caressing though neither was quite sure where one of them ending and the other began. Edges blurred, sensations merged and swelled with sweet synergy, and for a moment two minds become almost one in ecstasy.

In that brief moment of complete system-link, Breakdown's primed programs burst into action. The duplicate of Breakdown's cognitive code was cut and divided, some sections deleted at random while homologous segments were found and copied from Knock Out's, and both incomplete copies were spliced into a functional whole. The new programming was packaged and compressed then archived in Breakdown's memory banks, a new and unique set of cognitive programming that once upon a time would have been transplanted into a blank protoform. Breakdown's body would store the unique packet of code until his next cycle came around and then summarily delete it to make room for the next one.

For all its complexity, the link only lasted a split second. Then firewalls were re-established, cables disconnected and coiled back beneath their protective plating. Breakdown still tingled with Knock Out's presence, inside and out, and he sagged limply to the floor. An equally shaky Knock Out draped over him, nuzzling his neck and stroking his helmet.

"Next time, you come straight to me, mm?" Knock Out said, groping Breakdown's wheels. "I don't want anyone else thinking about laying so much as a finger on these sweet rims."

Breakdown snorted, but he was feeling far too content in the afterglow to try pushing his partner away. "You're impossible."

"You love it."

"Hn."

Slagging headlights.