Disclaimer: Transformers © Hasbro
Warnings: somewhat AU, fairly hardcore sticky mech smut, and allusions to mech-preg at a later date... which won't be written in here, yet I felt it should be in the warnings anyways.
Notes: Just for the record, this ain't romantic. Not by any stretch of the imagination. It's more lust and alien biology than anything else... but if that's what gets you going, who am I to argue? As a result, there's very little dialogue.

Again, this is rated M for a damned good reason. Turn back now if you don't care for the smut.


Cycles

He'd known it was coming, but had Cliffjumper realized that his heat cycle would hit in the middle of nowhere with only his least-favourite Lamborghini around for company, he would have begged off the scouting mission and locked himself in his quarters with only Mirage and Hound to "assist" him through it. But no, he'd thought there would be a few more days before he needed to worry about it and agreed to take Sideswipe's place on the run in spite of how poorly he got along with both twins.

So now the minibot was stuck trying to think of some way to slip off and take a bit of the edge off without Sunstreaker noticing. Given the way the big yellow menace had been keeping a calculating optic on him the entire morning, that seemed to be next to impossible, and if he didn't get away in the next several minutes then he was probably going to wind up giving the Lambo a crash course in Seeker-kin Heat Cycles 101.

"You okay?" Sunstreaker asked abruptly, something in his vocalization sounding... off, but not easy to place. He found himself blinking at the taller mech and absently wondering what would happen if he were to jump the larger mech and demand to be 'faced into the ground this instant.

Probably a thump to the helm and questions regarding my sanity. So, bad idea, Cliffy.

"I'm fine," Cliffjumper replied shortly, sounding as if he were trying to maintain control over himself. Sunstreaker narrowed his optics, not quite sure he believed the minibot. Then again, he was probably reading too much into the other mech's body language and energy field at the moment due to his own hyper-sensitivity.

Toughlines like himself and Sideswipe didn't have rut cycles very often - only when there was a viable breeder in the vicinity that had gone into heat - yet during their time on Earth both had slipped into rut three times for no apparent reason. They tried to take out their aggressions on one another, but still sometimes caught others up in the dominance fights. The worst part of it was, neither twin had any idea which of their fellow Autobots was setting them off; Red Alert would be a possibility, if not for the fact that he was bonded to Prowl and his heat cycles tended to fixate on his mate.

Yet here he was, systems cycling slowly over into rut and the only mech around within miles was the little red pain in the gear shaft that he'd always taken pleasure in antagonizing. And Sunstreaker was a Decepticon double agent if Cliffjumper's energy reading hadn't practically been screaming breeder in heat for the past five minutes.

The minibot growled to himself as Sunstreaker continued to watch him with an oddly calculating glint in his optics, his interface systems cycling online and insisting that it would be a very good idea to pounce the delicious-looking toughline. At the moment, his logic programming was focused on dealing with the heat and was in no condition to come up with a counter-argument.

A faint purring note came from Cliffjumper only a few second before he quite literally pounced on the Lamborghini, fingers digging between armour seams and giving off vibes that Sunstreaker recognized from his more recent rut cycles. If he had been thinking clearly, the idea of 'facing Cliffjumper would have been horrifying.

Well, okay, not horrifying, but also nowhere in the realm of possibility if only because of how similar their personalities were. However, he wasn't reacting to a semi-friend hitting on him out of nowhere but to a breeder in heat, and Sunstreaker acted accordingly. His interface panel opened with a rasp of metal, spike already beginning to slide from its housing as he rolled over and pinned Cliffjumper to the ground. He dropped his head to the minibot's neck and nipped hard at the wires there.

The smaller mech shivered slightly, not in any manner of fear but in anticipation, his own interface panel sliding open to expose the port already slick with lubricant and coolant. Cliffjumper shifted, thighs parting and gripping at his partner's hips as Sunstreaker bit his neck cables again. Another turn and shift from both, and the smaller of the pair let out a long moan as the toughline's spike sank into him.

Sunstreaker stilled, taking a moment to enjoy how hot and tight and wet his partner/temporary mate's port was around him, then with a low growl began to pound into the minibot. Cliffjumper's thighs tightened around his waist, blunt fingertips digging into shoulder plating as the submissive partner howled in pleasure. Sunstreaker's spike hit hard and deep every time, striking every node in his port and ratcheting his arousal up even higher. The instinctive drive to mate and breed clicked into hyper-drive, Cliffjumper absently noting when the reservoir located at the very end of his port spiraled open in anticipation.

Sunstreaker could feel when the slight resistance at the top of his partner's port gave way and snarled low in the back of his vocalizer, gripping the minibot's hips and driving harder into him. He was acting only on instinct now - the instinctive desire held in few Cybertronians to breed and continue their model line - and changed his angle so that the tip of his spike could slip through the reservoir opening. Cliffjumper arched with a drawn-out moan, body going limp and allowing his dominant to adjust him as he so pleased.

Neither one lasted much longer after that. Sunstreaker slipped one arm carefully beneath his submissive partner's lower back, tilting his hips up in order to drive deeper and breech the chamber fully. Cliffjumper let out another howl, fingers scrambling for purchase at the Lamborghini's shoulders as overload hit him hard and fast. Energy crackled in the air around them as Sunstreaker groaned and overloaded only a few seconds later, transfluid spilling from his spike into the minibot's reservoir. The pair collapsed fully to the ground, Sunstreaker just barely keeping his full weight off Cliffjumper as they cycled air through their intakes in an attempt to cool down for even a short while.

After several minutes, Sunstreaker shifted just enough to slide his spike part-way from the mini's port, feeling the reservoir opening spiral shut as he did. He could still feel the effects of his rut cycle, although momentarily dimmed, and knew that the instant Cliffjumper's heat notched up again that there would be a repeat performance.

Cliffjumper groaned softly and slid one leg to lie flat on the ground, optics slightly dim as he automatically checked his interface and reproductive systems. There was a viable amount of foreign CNA in his reservoir at the moment, although not enough to influence spark generation. After a few more rounds, it could become a real possibility, one that he hadn't needed to be concerned over until now. Mirage and Hound's CNA had too many common code lines with his, meaning that spark generation was impossible and the interfaces with them were simply to combat the heat cycle.

And yet Cliffjumper couldn't bring himself to worry about the possibility.

Thirty hours later, Sunstreaker and Cliffjumper returned to the Ark exhausted, filthy, and in inexplicably good moods. If anyone realized that some of the grime covering the pair bore resemblance to lubricant and transfluid, they didn't say a word about it.

Ratchet, however, had plenty to say a few months later. But that's a story for another time.


End Note: I have a sequel planned for this. It's turning out to be, uh, more of the same. So, yeah.