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“Kajii, I want you to help with my experiment.”
Your tone is blunt, simple. A straightforward proposition under the guise of a statement. The man turns to you, expression unreadable under those thick goggles he constantly sported. Tinted, nerdy - kind of endearing, you had mused. Something that would have resulted in a quick agreement if your experiment hadn’t been one revolving around sex.
A beat of silence, his mouth opening and closing, speechless. Strangely speechless. It was starting to jumble your nerves - maybe the tension between you two wasn’t as apparent as you had hypothesised. Kajii Motojirou and his dutiful assistant, that was the relationship that the two of you had begun with. Though, over the course of your time in the Port Mafia, it had seemed to bloom into something more. Kajii was an ever physically affectionate man, practically jumping on everyone he was friendly with - ruffled hair and excited grasps of hands.
Whenever an explosion went off, really, the man would jump in joy - excitement coursing through his veins as he practically launched himself at you; you had returned these affections - begrudgingly at first. He was in fact a strange man, some weirdo you had been nervous to work under when you were first assigned.
Feelings shift, though. Variables always have the capacity to change, to morph, to cause strange new outcomes - and you found yourself falling for the man. Well, finding him endearing at least, and wondering if he had ever had sex with anyone. He seemed so hyper focused on his experiments all the time you doubt that anything other than his own hand had travelled down his pants. The Port Mafia didn’t exactly provide the ideal environment for romance to cultivate, so a sort of primal attraction was more so the title that fit your desire for him. That’s how you found yourself revealing your attraction to him.
He had looked over your shoulder, spotting your notes on reactions - sexual reactions to be exact, the way the body biologically responded to the effects of sex. Ever curious, he questioned what you were studying that for, and you’d simply explained that the natural chemicals released might be useful to replicate artificially. The dopamine released by orgasm acted as a sort of pain reliever, and it’d be useful to harness those chemicals in the medical ward if replicated correctly. Asking him to help, you had ended up in this situation.
You had never seen the Kajii Motojirou this quiet. Boisterous, eccentric - hell, even annoying at times, and always talking. Rambling on about his experiments, something he referred to as his playtime with an almost disturbing glee. This was something he had no experience with, though. For a man so prideful about his knowledge, he was awfully stupid when it came to talking about sex.
“You want me to help…?”
“That’s what I said, yes.” A calm response to hide your nerves, the fear that a letter to the boss and an embarrassing repositioning would be due. Though, much to your relief, he nodded slowly. Ever the man of science, willing to partake in things he was unsure of for the pure search of knowledge.
“Okay…” His throat sounded dry. It was almost disturbing, seeing Kajii look so timid. Sure, when he was getting his ass beat he’d scurry away whimpering, but in his zone? A laboratory? Confidence was all he had. He continues, attempting to put on an air of professionalism - though it was obvious with the way he crossed his legs and nearly fell over trying to lean against a counter cooly that he was freaking out internally.
“What do I have to do?”
As you knelt between his legs - hands splayed on the pale skin of his thighs - he was, for a lack of better words - stupefied. You’d gone over the terms of the experiment : he was to be hooked up to a simple electroencephalogram, his brain activity recorded as he went through the different sexual stages. It was simple - he just had to sit back and relax and you’d collect the data for your own analysis. Though, he wasn’t doing much relaxing.
Getting him hard wasn’t an issue. In fact, as soon as you had asked him to aid with the experiment his face had flushed. His eyes had darted down nervously, and your eyes naturally fell on the fabric of his frayed jeans already stretched.
“I - um - haha! It’s not like I was getting aroused just by your question! The great Kajii Motojirou doesn’t -” His hands had come up, waving frantically in your face as he stammered out an explanation. You had simply raised a brow at him, explaining it was okay. You wanted him aroused for the experiment, which he responded to with more sputtering.
Your head now rests against his leg rather affectionately, and he practically jumps - staring down at you with his bottom lip between his teeth, eyes wide. You have to place your hands on his knees, holding his legs down because at the rate they’re bouncing he’s gonna end up knocking you out mid blowjob. Not an ideal outcome for anyone, really. Trial and error is necessary in experiments, but it’d be preferred if the error wasn’t a bloody nose and a shambled explanation to anyone who asks where it came from.
“Relax, Kajii.”
“Relax? Haha! I’m completely relaxed - I fear no method, no science will ever deter mn-”
His self assured speech is cut off when you finally hook your index finger under the hem of his boxers, (decorated in lemon decal, which would have made you laugh were you not face-to-face with his cock) tugging them down. His cock is exposed and - wow. You knew there was some sort of stereotype about nerdy guys packing, but it seemed like that bias was now confirmed. He was definitely lengthy, and also most definitely had no idea what to do with all that.
You don’t realize you’re staring until you hear him from above you, impatiently clearing his throat. His entire face is red, bordeaux flush seeping down to his shoulders, and coating the tips of his ears.
“Of course, of course. I’ll commence the experiment, then?”
You cringe internally at your own poor one liner. He doesn’t seem to mind.
You bring your lips to the head of his cock, flushed a bit darker than the rest of his length.
“Have you ever done this before, Kajii?”
Your lips brush against the tip as you speak, and he full out whines. Not even a simple touch, and he’s already providing some pretty intense reactions.
“Ah - um - no? Haha, I’ve um - I’ve never quite had the time for activities like th-this. Every second of my life is dedicated to s-science.”
His hips jut upwards as he speaks, and you have to move your head to the side to avoid getting hit in the face. He frowns at the loss of that contact, glancing down at you with his hands drumming irregular patterns on his thighs. An expected reaction, coming from an almost 30 year old virgin.
“Then you’ll be perfect for this.”
You hum, pressing a kiss to the side of his length. He shivers at that praise, clenching and unclenching his fists - unsure of what to do with them.
Yeah, no, it’s pretty obvious his only experience has come from his own hands.
You work your lips down the side of his cock, hands fondling his balls, pressing a kiss to the skin on the underside; All the while hoping the walls of the laboratory were soundproof - or at least thick enough to muffle the sound of his gasps and whines. A steady string of ramblings fall from his lips, jumbled phrases of, “Oh god, please please please keep going there,” and, “Fuck! Fuck, fuck…” Devolving into frequent whimpers and shallow breaths, moans ripped from his throat unabashedly. You hadn’t even taken him in your mouth yet, and he was a complete wreck.
It was almost satisfying to see him like this. For a man who’s ego often shot sky high, it was refreshing to see him in shambles, head lolling forward and back as his back arched, legs twitching, moaning pornographically.
When you do take him in your mouth, though, you nearly choke. While your hands rest firmly on his thighs to keep him from kicking out at you, (which has happened nearly too many times this session), his hips jut upwards, and you simply accept your fate taking his dick in your mouth. He lets out a loud, girlish whine, hand grasping at the back of your head for any sort of stability.
“Fuck, pleaaase please. You’ll keep going right? I’m doing so well, please, I’ll give you good results.” He rambles, and you give him a reassuring pat on his sweaty thigh to communicate - yeah, you’re doing well, your dick is in my throat.
He’s actually lasting a lot longer than you’d expected, and you have to come up for air, wiping your lips ungracefully with the sleeve of your lab coat. Kajii’s staring at you - or at least you think he is through the dark lenses of his goggles - his mouth ajar as he breathes in short gasps.
“Are - are you finished?” He sounds so sad, so pathetic, you can’t help but laugh.
“No, just needed a break.” You coo, hand wrapping around his length now, jerking upwards in a sudden motion that leaves him clenching at the arms of the chair he’s seated in, leather squeaking. You finish him like that, fist working in a repetitive motion, almost lazily - but he eats it up nonetheless, head thrashing as he repeats pleas of, ‘please,’ and ‘keep going, I’m doing well right?’
He finally cums with a loud cry, head tilting back as his hands grasp for purchase on the chair. Your free hand reaches up, taking one of his, and he accepts the tenderness with a shuddering whine. Cum coats your hand now - you’d have to wipe it off with a towel, definitely a biohazard in the lab.
Tucking his now softening cock back into his boxers for him, you stand up with a groan, washing your hands at a nearby lab sink.
Kajii, spent, from behind you, catches his breath.
“Did I perform well?”
It’s strangely unsure, coming from a man who loves to wax lyrical about his scientific triumphs and insane genius. Though, you supposed this was a field he had virtually no knowledge in.
“I’ll have to look at the data,” you begin, and he nods bashfully, pulling his pants up, “But I might have to replicate this test to make sure these variables remain constant - if you’d be willing to help me?”
You burst out laughing at the immediate agreement he shouts out, knowing he’d be the perfect subject for future experiments.