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“Aw, what’s wrong, doctor?” Knock Out mocks, pushing you down to straddle his spike. “Cat got your tongue?”
You summon all of your strength not to call him a cunt. He’s a marvel of technology and biology alike, a form so perfect you can’t even dream of recreating it. Your employment at M.E.C.H was short lived, but you’re half tempted to call them up and beg them to seal Knock Out’s intake shut if it means you get to examine him in peace.
It took only a few lascivious offers from Knock Out for you to agree to it. Initial amazement at his spike and valve quickly turned to forlorn resignation when he picked you up, undid your pants with dexterity a creature of his size should not have, and tossed them so far away you would have to jog a whole block just to get there. When you said you wanted to learn about his inner workings, you didn’t mean “Wear me like a cockring”.
“Really doctor?” he starts again, shoving the PHD you mentioned right down your throat. “I thought you were eager to ask me questions pertaining to, ah… the entirety of my anatomy,” he croons in that stupid sexy voice that could make billions on asmr youtube.
“I am,” you scoot farther from his spike and into his lap, “but I didn’t ask to be an active participant-” he scoops you up and places you back on his member, facing away from him.
“What,” you croak out, confusion oozing through your core leaving you all cold and sweaty.
“I thought we agreed to do this on my terms?” he says, not quite a question, more of a statement.
You look over your shoulder and shoot him a “You can’t be serious” expression. His cocksure smile widens.
“Fine,” you concede like a teenager being nagged into throwing out the trash. “But once this is over, I want all your fancy schematics on Cybertronian anatomy. All of it, without the shitty child locks blocking the articles.”
He feigns contemplation, making a show of tapping his chin and glancing up at the ceiling.
“I don’t know,” he drawls, “it took me millions of solar cycles to access them at the Medical Academy.”
He jerks up and almost swings you off when you palm the head of his spike, your smugness reduced to ash as you’re forced to hug it for dear life, much like a koala, flashing him in the process.
“You-” he trails off into silence, then you feel a digit ghosting over your sex.
“DON’T YOU FUCKING DARE,” you shout before he so much as thinks about it, adjusting your grip on his package and swinging your legs over it to face him. “We are not doing any of that without lube, so unless you want to cut things short and make a trip to the pharmacy and get accosted by at least five people asking questions about my European model car-”
He smirks.
“Shut up, no - we are not doing this and that’s final .”
“Fine,” he yields, leaning back against the wall all casually. It gives you the unnerving feeling you’re staring at a cat, predatory optics boring a hole through your very soul.
“You know,” you say, shifting the topic, “I was wondering, how does your spike pressurize?” His mechanical irises dilate and he flashes you his fangs.
“Back to business as always, doctor.” You violently suppress a cringe. “You see,” he gestures at the now softer, cushier metal plating of his groin, “in order to reach optimal pressurization, our protomatter must collapse in on itself much like, say, our servos transforming into weapons. This reveals our protoform-deep hardware, and with it, our spike panel.” If you squint hard enough, you can see the barest traces of said panel around the base of his spike.
“Okay,” you draw out, reaching out a hand to trace it. He shudders and swats it away.
“No touching is allowed during the lesson,” he hisses, vents running on 70%. “But if you’re so inclined” he gives you a cat-ish leer, “there’s a hands on exam right after.” He unnecessarily clears the throat he doesn’t have, his engine emitting a light rumble. What a fucking poser. “Now,” he starts again, “the pressurization process requires the fuel lines situated in our spikes to pump energon and stretch the excess plating into its new, leaner shape. As it pressurizes, the interface panel opens up to allow the completion of the transformation.”
“Sort of like how blood rushes into a penis?” He furrows his optical ridge like he’s about to start puffing up and hissing at you.
“Can a human penis prematurely exit its panel and painfully press against the pelvic plating?”
Silence.
“No, I didn’t think so. Just so you know, repeated instances of panel failures may originate from Machanimus Disjunctus or, in the case of older mechs, metal fatigue.”
You nod as though you understand any of that.
“Considering our past meetings, I assume you want to know more about our valves, hm?” he purrs languidly. “Your heart is beating faster, doctor. Are you growing impatient?” In a split second, he’s back to looming over you, holding your little chin in his massive servo. You summon all the strength you have not to melt into his touch. “Hm, no. I shouldn’t postpone our lesson.” He pulls away from you, and you’re left sticking your chin out in the air like a 20s mobster. Fuck.
“Our valves emerge from the lower panel. Their surface consists of metalmesh, perfect for cushioning; it prevents us from scraping paint during interface. The valve lips consist of dermamesh, it’s pliable and can resist quite an impact.” You have the innate feeling he’s alluding to his own experiences. “The innermost layers consist of internal pistons, they serve to contract and extend the valve and help it assume its normal shape after interface. On the subject of transfluid ,” he croons, emphasizing the subject matter by stroking the tip of his spike and coming back with a neon blue liquid. He brushes it between his index and thumb, then separates them, a trail connecting the two digits. Its consistency appears similar to honey in thickness and weight, nevermind stickiness.
Knock Out has the audacity to press it against your lips, and your dumbass self has the self-control of a cougar at a frat party. You go down on his digits like you’re deepthroating a corndog, and immediately wrench back from the taste.
“What the fuck,” you slur, transfluid prickling your mouth like a double A battery.
“You like it?” He laughs. The very same digit you were slobbering all over goes to boop you on the nose. “Transfluid is essentially transformed energon. Our fuel pump separates it into different categories. We have basic energon acting as our, for lack of a simpler word, energy source, keeping us functional and whatnot – then, its sub-products. You’re already familiar with transfluid, but we also produce natural lubricant for our joints. Might I inform you, cosmic rust shuts down our fuel pump’s ability to produce said lubricant, while a more benign condition like rust rash only limits it.”
You narrow your eyes at him. “Can you consume transfluid?”
“As a fuel? Certainly not .” He seems offended at the mere notion of it.
You narrow them even harder. “Is your transfluid going to kill me?
“Probably not,” he shrugs. Best case scenario, he’s just teasing you. Worst case scenario, you’ve ingested poisonous alien cum. “The biolights however,” he continues nonchalantly, “act as an enticer for the potential partner.” You glance down at the disco light mating display.
“These aren’t the only biolights you have,” you sternly point out. “What about those on your back and waist? They were glowing until your interface opened up. Are you… are you telling me you’ve been flashing me in front of others?” you whisper incredulously. All the nasty looks the others gave Knock Out weren’t because he was an ex-Decepticon. They were rightfully offended at him doing the Cybertronian equivalent of palming his crotch and sizing you up. You are never going to live this down.
He shrugs again, grinning wider than a Cheshire cat.
“That’s about as much as I can break it down for you, even a newly forged Cybertronian can understand that. Or are you hungry for more?” he asks with a salacious lilt to his voice.
You file your newfound humiliation in the “for later” drawer, gaining enough composure to roll your eyes at him so hard it makes your brain hurt. He better not make you regret this, you’ve lost enough dignity from his antics alone. The plan is simple, cum at least once, get the documents you want, then file for sexual harassment with Ultra Magnus.
“Yeah no, let’s stick to the actual sex so I can get my hands on those anatomy archives.” He leans over you like a predator, optics glinting with hunger.
“Very well then,” he wraps a servo around your waist, shit-eating grin growing wider than ever before, “let’s rattle.”
You brace yourself against his servo as he rubs you up and down his spike, pressing the tip against your entrance and coating you in his (possibly poisonous) transfluid. He makes a show of throwing his head back and groaning, which, to your utmost chagrin, makes you wetter than Niagara Falls.
“Fuck,” you hiss, the coils of his spike pressing up against sensitive nerves and sending a shot of pleasure through your core that has you shuddering in his grasp. Antenna-ears pulled back, he looks all manners of pathetically cute as he grits his denta and fucks your body with his spike. He pulls you away, earning a whine of protest, and gets to his knees. His massive frame eclipses the ceiling lights of the base, optics glowing menacingly above you with his spike draped over your body. You do the sane thing and wrap your arms around it like a cherished body pillow.
If the Autobots find you two fornicating in the supply closet, Ultra Magnus will have your head and divorce himself from humanity altogether. Oh and Knock Out too, you guess.
Right now, the pleasure is too intense to give a damn. Heat pulses between your legs as his warm member pushes against you, transfluid dripping onto your cheek. Your hands trace the various ridges, fingers running over the white underside and rubbing the cherry red plating at the top. He shudders, optics flickering and giving you the impression he’s actively holding himself back from using you as a fleshlight. Instilled with newfound smugness, you drag your tongue across his spike, slow languid licks that have him growling above you between clenched denta. If looks could kill, you’d be buried six feet under. He quickens his space, transfluid leaving a trail from your cheek to your thighs, you’re starting to feel like a marinated chicken. Angling your hips to meet his spike, you let him work you up, member dragging over your leaking sex enough to make your thighs shake from the heat pouring into you. A high pitched cry escapes your lips as you come undone, gripping onto his spike for dear life as he fucks your body into oblivion. His biolights flicker, and you’re accosted in a moment of pure orgasmic genius with the worst idea in your life.
You push a finger into his spike.
Right on cue, he yells, overloads all over your face, and gives you the most bewildered glare you’ve ever received, cockiness as equally drained as his spike.
“You…” he starts, blue in the face. Bluer than the transfluid coating your skin. “What the fragging fuck was that about?”
“Uh,” it's your turn to shrug. “Instinct I guess.”
“You GUESS? Primus, I saw my life flashing before my optics!”
“I guess you're into urethral sounding?”
“Please don't use that word ever again.”
You send him a sheepish smile. “My bad, doctor.” He's looking at you like he's torn between killing you and rawdogging you to the Well of Sparks and back.
“Can you grab me a towel?” you ask, wiping the transfluid from your brow for emphasis, you’re wetter than an Olympic swimmer at this point.
“I don't know,” he snaps, “can you restore my dignity?”
“You have dignity?”
You've done the impossible, he actually stammers over his words, unable to form a funny quip for once in his life, rage building in his optics like a murderous kitten.
“I'm kidding,” you pat his servo non-apologetically. “I loved my first time getting a facial from a dick my exact height and weight.”
“Oh frag off!” he snarls good-naturedly, at least by Aston Martin standards. Much to your surprise, he withdraws a towel from his subspace and flings it at you. It smacks you right in the face. You look down at it. Then up at him. Then down. Then up.
“Did you actually plan all of this from the start? Wait, for how long have you been carrying it?” you ask incredulously, brain wrinkling just wrapping your thoughts around it.
“Why obviously!” He puts an offended servo to his chassis. “And a little over a week,” he adds cautiously. “What? You won’t accept it?”
“Of course I do,” you say, muffled under the towel you're wiping your face with. It's covered in his blueberry paste. And glowing. “I appreciate the gesture.”
Once you're at least 90% human, he cups you in his servos and presses you to his cheek plate so fast you’re left reeling from the shock.
“Wait, what about your finish-?”
“Shut up and enjoy this before I change my mind.”
You’re not one to look a gift horse in the mouth, or a hot piece of Cybertronian aft in the valve. So you do as you’re told and lean against him, vents blaring so hard it feels like a sauna. His cheek plate is warm and unusually soft to the touch, exactly like… Dermamesh .
Maybe it’s the trickling of transfluid down your thighs, or maybe the incredible safety you feel being cradled by a being millions of years old… or maybe it’s L’Oreal pushing you to french kiss him, self-preservation wiped away with the rest of his blueberry mush. Clumsy but determined, wearing your “I am inexperienced” badge out in the open, you kiss him like you’re in a wine’s mom favorite romcom, but much, much more challenging with a partner at least six times your size – feeling more naked than you ever did when he was fucking you. He pauses for a long incredibly drawn-out moment that has you thinking “Crap, was this too far?” with blood pulsing in your ears as the dramatic romcom music picks up. Then, in a flash of passion, he kisses back, baffling you with his own inexperienced kisser badge, and it finally hits you. Oh shit – Cybertronians aren’t used to this kind of stuff. It must feel like fondling someone’s weenus! But lucky for you, Knock Out wants you to fondle it, especially with a secret weapon up his proverbial sleeve: no lungs.
You pull away for air, wheezing like an idiot because your lack of self-preservation has brushed off the most important bodily function and ruined your romcom moment.
“I didn't expect you to be that bold,” he teases, ruffling your hair with a digit, only to wince when his white finish turns a neon blue.
“Yeah,” you snark, “and I didn't expect you to paint me blue.” His engine snorts for him. “Can I get my pants back, though?” you ask, thumbing at the discarded, clean, and you really mean it when you emphasize, clean , pair of cargo pants. “I'm getting cold.”
“Aw, aren't I hot enough for you?” he whispers against your neck, and you would be aroused if he didn’t ruin the pun by blasting his vents in your face, hands shooting up to shield your eyes.
“Cunt,” you call out under the blaring.
“Why thank you, I have a pretty valve if I do say so myself.” He flashes you one last cunty smile before tucking you under his chin and against his chassis. You stay like this for a while, enjoying the soft heat of cooling vents not blasting you with the force of an air dryer on the Plus Ultra setting. You would have fallen asleep against him in your blueberry-tinged clothes if a sudden thought hadn’t bitch-slapped you across the face.
“What about the files?”
“Oh, hm.” He clicks his glossa. “Ask Ratchet.”
You almost shoot up and uppercut the bitch, only to be pinned between his servos. “ARE YOU FUCKING KIDDING ME?” you yell under his chin, eyeing his neck cables like a rabid beaver. “HE’S HAD IT THIS ENTIRE TIME?”
“Well, shortly after defecting from the Decepticons, most of our – er – their database was destroyed, including…” he shakes his head wistfully, “ a valuable number of documents dating as far back as the Golden Age. Whatever the Autobots – I mean we – managed to retrieve were left in Ratchet’s care as the new…” he lets out a forlorn ex-vent, “Chief Medical Officer.”
Your jaw doesn’t fall, it drills through the ground and into the Earth’s molten core.
“Don’t look so disappointed, you can access them just fine with help from yours truly – I promise to put in a good word for you. Don't you worry your pretty little head.” He hooks a digit under your chin and closes your mouth.
“Knock Out, I’m going to piss in your intake.”