Warnings: mild BDSM themes (non-explicit) and deals with humiliation as sexual stimulation... and I suppose I should warn for robots having a sex drive too. Never change, fandom.

It felt like he was being watched. No… that was incorrect. Even standing still, it felt like being pursued. It made his spark pulse increase in pace, and the box of delicate slides he was holding nearly slipped from his grasp when he realized it. He didn't know how he knew that his pursuer was approaching. It was an interesting phenomenon –

There. A flash of red, darting between the rows of supplies hidden in the half-ruined underbelly of the Ark that served as their supply locker. There, and then gone again. But Perceptor had noticed. The trembling started deep within his frame, perhaps in his very spark; the box of slides shook slightly as he replaced them on the shelf. There was no time to ensure that they were put into their correct position… a fact that perversely thrilled the scientist even more as he turned to wait, head turning left and right to passively scan the area.

Predictably, his stalker struck from behind. There was only the smell of burnt tires and fresh wax to warn him, but the whiff of scent was only a moment ahead of its owner, and Perceptor was soon caught up in possessive arms. There was a hot engine pressed against his back, and he found himself relaxing into it.

"Here…?" he murmured, uncharacteristically succinct in the face of danger. His spark was pulsing noticeably now. The mech behind him growled his engine – a beautiful sound, Perceptor thought dimly, well-maintained and powerful – and leaned down to nuzzle roughly at the side of Perceptor's head. "No. We're going for a ride."

Perceptor's shudder was answer enough, and it made the mech laugh. Cruelly, Perceptor thought, but even that wasn't without its charm.

Charm. That's all his partner was made of. From the very first, it had been what lured the scientist in, then what disabled him, and finally it was the cage he never thought to escape from. Perhaps the doors were waiting, wide open, and he just didn't notice…

Perceptor shook his head. Since when had he become poetic over so simple a thing? He liked what Sideswipe did to him. There really was nothing deeper than that.

He was released suddenly and staggered forward a bit as Sideswipe transformed behind him, his passenger door swinging open upon completion. Perceptor knew his task, but waited for the order with anticipation until Sideswipe growled "Get in already," impatient to get going and knowing well enough that the scientist didn't have to be coaxed… but that he enjoyed it.

Perceptor was quick to transform and land in Sideswipe's interior when the order came, and was not startled at all when the door slammed shut, locking him in, and the engine roared, tires squealing for traction against the smooth floor before they finally caught and Sideswipe lurched forward. What surprised him was the seatbelt that slid over him, laying over his eyepiece tube and stage, securely pressing him back against the seat.

"Are we going somewhere particularly-"

"Be quiet."

He fell silent.

The scenery of the Ark's hallways blurred, slowed, and blurred again as Sideswipe tore through the passageways. Perceptor could still see, in a sense, though his optics were subspaced. It was an interesting experience, to be able to see things from Sideswipe's point of view. The face of an Autobot snarling at him from above after nearly being run over by his recklessness. But then, speeding away. None of them could catch up. It was freeing.

Abruptly, Perceptor remembered. "Sideswipe! My lab, we have to stop at my lab!"

"No."

Perceptor wavered. On one hand, he was highly inclined to acquiesce, to give up to Sideswipe's desires. But…

"I seem to have forgotten them," he whimpered, and the annoyed rev of Sideswipe's engine was rebuke enough. But they were stopping.

Perceptor was quick to transform and scurry into his lab, all the while looking over his shoulder, spark still pulsing, expecting at any moment Sideswipe would lose patience and come in after him. That was an exhilarating thought.

Nevertheless, after he had quickly gathered up what he needed and bundled it into a discreet cloth, he found Sideswipe waiting outside, rocking back and forth on his tires slightly.

"Put it in."

Perceptor was honestly taken aback. "You… you can't mean right here?"

The annoyed engine rev meant yes, right here.

"But!" Perceptor sputtered, his spark pulsing faster at this new mortification. "It's… anyone may encounter us and observe-"

"They'll observe what happens when you don't do what you're told in a minute, and that's much worse, believe me."

Perceptor shuddered, glancing up and down the hall, senses strained for the noise of anyone approaching. But slowly, he loosened his armor and, baring what was underneath it to the empty hallway, slipped one of the devices in.

It was an overload inhibitor. They became necessary, after their first drive...

Once again transformed and secured in Sideswipe's seat, Perceptor finally let himself go. As they sped through the entrance of the Ark and into open desert, Perceptor felt his spark leap. Even the stars above them blurred as Sideswipe rattled across uneven terrain until he found a paved road – and then really let go.

Even in his altmode, Perceptor's plating shifted restlessly. The pressure, the knowledge of how fast they were going… For a normally sedentary model, this kind of speed was unthinkable. For most, it would be terrifying. For Perceptor, it was nothing short of arousing. He groaned quietly, relishing even in Sideswipe's sharp, mocking laughter.

They swerved around a truck that blared its horn at them, and the inhibitor did its job.

"Sideswipe," Perceptor murmured, barely audible over the rush of wind and his partner's engine. "Sideswipe, please."

"No."

Even the denial was arousing, now. Perceptor rocked behind the restraining seat belt, only half-trying to get his wits back about him. He didn't want to think, not really. This was not the time for thinking.

By the time Sideswipe deigned to stop, Perceptor was trembling non-stop, itching to get out of his altmode, to touch himself, to do anything that would get rid of this ache-…

The warrior ejected him roughly and transformed, finishing a split second before Perceptor. It was all he needed to stand and pin the transformed scientist with his pede. Perceptor looked at the pede on his chest with overly bright optics, his expression already halfway to blissful stupor. Sideswipe grinned down at him.

"Why do you keep doing this, Perceptor?" He slid his pede up along his captive's chest, close enough that Perceptor was getting a real good look at the tire on his ankle joint. "You got my tires all dusty. Clean 'em off."

As Perceptor obediently licked – even with a look of disgust – Sideswipe continued. "You're gonna make a 'bot think you like being degraded. Is that it? Hah, that'd be funny, Perce."

Perceptor hated that name. He kept licking, nudging the tire with his face to get it to spin, and acquire access to more disgusting dust. Suddenly, Sideswipe crouched, and Perceptor's plating protested with a creak that had the scientist whimpering a warning. But Sideswipe didn't put enough pressure on the mech to crack his rather weak armor. He had only crouched to lean in close, grinning again, and whisper cruel words.

"The smartest Autobot in the universe," he purred. "Gets off on going fast and being used for his body. Do you even know how funny that is?"

Perceptor moaned and tried to squirm, but Sideswipe knew this game too well. "You know I don't love you, right?"

Why was this coming up now? "I don't care," Perceptor groaned.

"… Good." Sideswipe rubbed his tire on Perceptor's face. "Good 'bot." Perceptor loved it, and Sideswipe knew it. Even when he stood and lifted his pede off Perceptor, the mech didn't move. He knew not to. "You made me stop," he accused Perceptor calmly. "To pick up things I told you to have on you at all times."

"I'm sor-"

"Hand them over."

Perceptor wanted to open his armor right there, but instead meekly retrieved his cache from subspace and handed it over. Sideswipe sneered at him and kept his arms crossed over his chest.

"Idiot," he snapped. "With your mouth. Pick it up with your mouth and put it at my pedes. How stupid are you?"

The inhibitor blocked another overload that had Perceptor arching off the ground. When it passed, he moved to obey, setting his cloth-bound package of implements down, flipping himself over, and picking it up with his mouth. Or at least trying. It was all bound up neatly in a knot, but trying to avoid getting another mouthful of dust was impeding his progress. After a couple of tries, Sideswipe lost his patience and pressed Perceptor's face into the ground fully.

"Do you see this?" What a stupid question, of course he saw the ground, his face was pressed right against it. "This slagging organic dirt is more useful than you are. Say it. Say you're lower than the slagging dirt."

"I… I'm lower than dirt," he whispered, spark hammering out a rapid pulse.

"That's right." Sideswipe released him all at once and stepped back again. "Now do it right this time."

The bundle was laid at Sideswipe's pedes, and Sideswipe's pleased murmur or "Good 'bot" and a caress on the head had Perceptor shaking again. Watching as Sideswipe opened it and carefully chose something was tantamount to torture. When he finally chose one, he simply smiled and tossed it carelessly to Perceptor. "Use this. And don't you dare take that inhibitor off, you greedy slagger." And then, just to taunt Perceptor further, he opened his own plating to pleasure himself while watching.

Still, Perceptor obeyed. Even as this newest toy had him writhing and babbling, he couldn't overload, could only focus on what Sideswipe was saying.

"You must love this, huh?" he was saying. "Stop pretending you're so much smarter than the rest of us. You get to be the toy you were always meant to be, right?" Perceptor moaned helplessly. "Thought so. I know you like it when I tell you you're just a filthy pleasurebot made for this. You should see yourself. Rolling in the dirt trying so hard to overload…" At Perceptor's pleading, desperate keening sound, Sideswipe smirked. "Pit, you really do want to get off. Alright. Alright, Perceptor. Calm down."

Easy enough for him to say, he had already overloaded once…

"You can overload…" Sideswipe was saying. "If you try to mate with that tree thing over there like an organic."

Perceptor stopped entirely, optics flickering with growing awareness. Had Sideswipe really just jolted him out of his haze for that? The same, insufferable smirk said, yes, he had. Just for his amusement. And that Perceptor better oblige him, or this would be a long night.

Pouting and glaring as intensely as he could, Perceptor stood – or wobbled, more like – and saw the downed tree Sideswipe was referring to. Presumably, his mas-partner wanted him to straddle it and rub against it. It would do absolutely nothing for him except humiliate him.

Which was the point, really.

The bark crunched under the metal of his thighs, and a burning shame settled in his spark as he began moving back and forth across the surface. It produced an unpleasant sound as all the bark was scraped off, but he kept going. A glance at Sideswipe confirmed that the mech was watching intently.

"There's a good 'bot," he encouraged. "Keep going. Pfff. You look ridiculous. That's just how desperate you are, I guess. I've seen petrorabbits with more pride than you."

To Perceptor's immense mortification, Sideswipe's words were arousing him again. Arousing him as he tried to mate with a log. It was ridiculous, and degrading, and he was going to overload so soon…

"Alright, get off it now. It needs a break."

Perceptor slid off it and collapsed in a heap on the ground, panting to keep his temperature down. And then, the words he had been waiting for: "Go ahead and overload now. You earned it."

He nearly tore his armor getting it open and removing the inhibitor. But once it was gone… he sat there senselessly, frustrated for an overload. Even as he touched himself, there was none coming. Sideswipe's laughter taunted him again.

"Come on, you boring glitch," he taunted. "I said overload. It's not enough when I tell you to? I've gotta tell you what a disgusting, needy, whiny glitch with open-plating you are? Or should I tell you about how next time, I oughta just leave you bolted to a table in the rec room with a sign that says 'free to use', because nobody's gonna pay for that-"

Perceptor overloaded with a wail, collapsing entirely, optics dim and unseeing as Sideswipe approached him, picked him up, closed his armor for him. "You're a kinky little bit, you know that?" he murmured to the half-conscious scientist, who only mumbled in response, systems rapidly shutting down. "Maybe one day I'll get to actually touch that. What do you think?"

Perceptor was quiet. He had fallen unconscious. Sideswipe sighed, and began the long trek back to the Ark. "Yeah, thought so."