Work Text:
Well. This is new.
Atsumu stares at his surroundings, blinking like a deer in headlights at all the brightly lit control panels and alien-looking tech in the round room he's standing in. He remembers being outside in his back yard, enjoying a warm summer evening with a beer and a podcast. Then there was a flash of light, a swooping feeling in his gut, and now he's… here. Wherever here is.
"Greetings, human. Please remain calm, we mean you no harm."
Atsumu spins around and finds himself face to face with two… aliens? The word sounds absurd in his head but he can't think of another that fits. They're humanoid but about 7 feet tall and built slimmer than any normal person, with skin shifting in green and grey and completely black eyes, sclera and all. They're also wearing what looks like lab coats.
"Uh… hi?" Atsumu says, trying and failing to conceal his shock and surprise. "Where am I?"
"You're on a small research vessel," one of the aliens reply, taking a step forward. The other remains silent and still, just watching. "My name is Rintarou but you may call me Rin, and this is Kiyoomi. Might we ask your name, human?"
"Sure, ya can call me Atsumu, but what am I doin' here?"
"Like I said before, we promise we mean you no harm," Rin says, pushing a few more buttons and turning towards the centre of the room. A soft mechanical whirring starts and a hatch in the floor opens up, revealing a sterile white table that's slowly rising. "We're here in the name of science."
Atsumu watches the table rise and shudder to a stop at about hip height, swallowing when he notices the four restraints attached to the sides of it. "And what kind of science would that be?"
"My partner here can explain it better, he's in charge of the study," Rintarou says, gesturing towards Kiyoomi before turning his full attention towards the control panel, adjusting slides and dials that Atsumu can't even begin to guess the function of. He shrugs off the thought and turns towards the other alien, whose impossibly dark eyes seem like they're staring into his soul.
"I'll be blunt," Kiyoomi says, and Rin huffs a quiet as always that goes ignored. "We need seed from a healthy human male, and you were chosen as a good specimen."
Atsumu's head is spinning a little. Seed? They need him to… and good specimen? He can't deny that that description is definitely stroking his ego. He rubs a hand across his face, trying to gather his thoughts.
"What are ya plannin' to do to me, exactly?"
"I understand your concern, but please be assured we have no intention to force you," Kiyoomi says, taking a few steps closer until he's standing beside the table. "We want to gather your seed as naturally as possible, through a climax brought by pleasure."
Something tingles low in Atsumu's stomach but he pushes it down, because there's another burning question on his mind. "Okay, but why?"
"Simply put, our people struggle with reproduction," Kiyoomi says, and there's a sadness in his voice that tugs at Atsumu's heartstrings. "Your species is the most similar we've found to our own in regards to anatomy and biology, so it's been decided that studying your reproductive fluids would be beneficial to solving our problems."
Reproductive fluids. Why is Atsumu so into the clinical way this alien speaks? He glances at the table, and a picture of himself strapped tightly to it flashes in his mind. He swallows around the pulsing heartbeat in his throat.
"And, uh, how is this gonna work?"
"You'll undress and get on this table, then we'll strap you in," Kiyoomi says casually, and Atsumu tries to pretend his blood isn't rushing south. "After that, it's up to you to tell us how to make you climax."
"Um," Atsumu says intelligently, shifting on the spot as he feels his dick start to fill out. "Ya'll restrain me even if I get on there willingly?"
Kiyoomi nods. "It's part of our safety protocol. Do you object?"
Atsumu doesn't even have to think about it. "Nope, not at all."
"Good, then that's settled," Rin suddenly chimes from his spot by the control panels, and Atsumu almost jumps out of his skin because he'd forgotten he was there. "The room has been calibrated to maintain a comfortable temperature for you even without clothes, so please undress when you're ready."
Atsumu's eyes flicker from Rin to Kiyoomi, who simply nods once, and heat rises in Atsumu's face as he starts to pull his shirt off. He's dressed in loose comfortable clothes, just athletic shorts and a t-shirt, so it doesn't take him long to shed them. When his fingers hook into the waistband of his boxers he hesitates for a moment, but the aliens' eyes on him are intense and unrelenting and Atsumu definitely needs to do some soul searching later about why he's so into this. The underwear falls to the floor and then he's as naked as the day he was born, hands instinctively coming up to cover his half-chub.
"There's no need to hide, Atsumu," Rin says, stepping close to mirror Kiyoomi's position on the other side of the table. "We're about to see you at your most vulnerable, after all."
Atsumu takes a deep breath, lets his hands fall and approaches the table.
Let's do this.
👽👽👽
"Are you comfortable?" Rin asks as he places the final sensor on Atsumu's temple. "Anything pinching or painful?"
Atsumu's not sure how to answer that. He's definitely a bit embarrassed about being naked on all fours in front of two aliens in buttoned up lab coats, but he's not in any pain. About a dozen small metal sensors have been placed methodically across his body and the ones on his nipples pinch a little, but he's not about to admit out loud that he likes it. The restraints are surprisingly comfortable and have some give to them, so he can move his legs a little and also choose whether to rest on his hands or his elbows. There's also what looks like a glass receptacle placed on the table, about the size of his hand with low raised edges. It sits right under the tip of his cock, and he shudders when he thinks about what it's for.
He's also fully hard at this point, trembling with anticipation and unsure if his voice will hold if he tries to speak.
"I'm good," is all he manages to say.
"Glad to hear it," Rin says, straightening up and moving to stand right in front of Atsumu. Long fingers curl under his chin and lift it up, making him look straight into those endlessly black eyes. "Now, Atsumu, what's the best way to make you orgasm?"
"My ass," he replies without thinking, shivering when Rin's fingers gently tighten around his jaw. "Finger me, fuck me, please."
"That can be arranged," Rin says in a low voice, letting go of his chin and stepping out of view. "My partner will explain the sensors to you while I get started."
Atsumu looks over towards Kiyoomi, who's stepping closer while focused on a holographic interface projected from a device around his wrist.
"This tracks the state of your body, focused on level of arousal, as monitored by the sensors we've placed," Kiyoomi explains, gesturing to the interface which looks incomprehensible to Atsumu's eyes. "It's for your safety and also to make sure we're on the right track."
There's a pause, then Kiyoomi speaks again. "It shows that you're already at a significant level of arousal."
Atsumu feels like laughing. What is he even supposed to say to that? This is all new to him as well, he had no idea he'd respond like this to being abducted by aliens and asked for his cum. Luckily, Rin returns before the silence can turn awkward.
"I'm ready to begin," Rin says, and there's a snap that sounds very much like a latex glove against skin. "I will stimulate your erogenous zones until you climax, and Kiyoomi will monitor your vitals and provide additional stimulation if required. Do you understand?"
"Uh-huh, yeah" Atsumu says, letting his head fall between his arms and bracing himself. "C'mon, do it already."
"Very well," Rin says, and Atsumu swears his voice just dropped an octave. "I'm going to touch you now."
The moment a slick finger grazes his hole, Atsumu falls from his hands to his elbows with a groan. He's already worked up and sensitive just from the anticipation of what's going to happen, and finally being touched feels like heaven.
"He likes it," Kiyoomi says from somewhere on his left, accompanied by a few beeps from the holographic interface. "Heart rate is spiking, more blood rushing to the area."
Being given a play-by-play of his own arousal should be mortifying, but Atsumu doesn't even have time to be embarrassed before a single finger breaches him. The aliens' fingers are longer and thinner than humans so there's not really any stretch, but Atsumu knows Rin's going to be able to reach deeper inside of him than any human. His cock twitches at the thought.
"Relax for me," Rin hums lowly, and Atsumu takes a few deep breaths. He unclenches his hands and tries to do the same with the rest of his body, and it seems to work because soon there's another finger prodding at his entrance. The two work in tandem for a moment, slowly fucking him, and Atsumu has to bite his lip to keep from moaning like a wanton whore. Fuck, how does it feel so good when Rin hasn't even grazed his sweet spot yet?
As if on cue, the fingers curl and find it almost immediately, sending a fresh jolt of liquid heat through Atsumu's body. He can't hold back his noises this time, moaning and cursing out loud, and the aliens seem pleased.
"The prostate gland is a source of great pleasure for human males," Kiyoomi says, and Atsumu's not going to argue with that one. "Keep up what you're doing and it won't be long before he spills."
Once again Atsumu should be embarrassed about the implication of the words, but he's distracted by yet another finger being introduced. Rin keeps up his slow but steady pace, massaging him in just the right way, and Atsumu can only close his eyes and take it. Embarrassing or not, Kiyoomi's right - it won't take long before he comes like this.
"He's so warm," Rin muses, and then there's another hand resting on his hip. "Makes me wonder, you know, what it'd feel like?"
There's a beat, and then Kiyoomi speaks. "You know we're only meant to do what's necessary."
"I know, but he did say we could," Rin counters, digging the fingers on his free hand into the flesh of Atsumu's ass. "Look at him, he's loving it. I bet he'd love it even more if I used all of me."
Atsumu turns his head to look at Kiyoomi, whose eyes flicker from him to Rin and then back. "P-please, want it."
He accompanies his words with spreading his legs as far as the restraints allow and pushing his ass back against Rin's hands. Both aliens gasp in unison.
"Oh, what a sweet human we found," Rin purrs, withdrawing his fingers. "Kiyo, unless you're planning to use your authority to stop me, I'm going to enter him now."
There's a slight twitch in Kiyoomi's face but then his eyes find Atsumu's again, and holds his gaze as he speaks. "I won't stop you."
Rin makes a triumphant sound and it only takes seconds before something else is pushing against Atsumu's hole, something thicker and heftier, and he gasps when Rin starts to push in. It feels a bit thinner than a human dick at first, but it clearly flares towards the base which is causing a delicious stretch. There are also some ridges and bumps along the shaft, and the way they catch on his rim and tease his prostate feels nothing short of incredible.
"Yeah, yes, fuck me," he babbles between ragged breaths, sinking down until his cheek is against the table because his arms simply won't support him anymore as Rin starts to move. "Give it to me, fuck-"
"Such a good human," Rin pants behind him, grip steady on Atsumu's waist as he rolls his hips. "So sweet, so tight, so perfect."
Atsumu opens his eyes just enough to look at Kiyoomi, who's still watching him intently. Then, without saying anything, he raises his hand and presses something on the holographic interface. The sensors pinching Atsumu's nipples buzz to life, sending shocks of pleasure into his core, and his shout of surprised pleasure echoes in the room.
"Oh, you bastard," Rin groans, clinging on tighter as his thrusts speed up. "You did that on purpose, he just tightened up so much."
"I'm only helping to speed up the process," Kiyoomi says, and Atsumu can't argue because he's quickly approaching the edge. His cock is dripping onto the glass receptacle, twitching and aching, and he frantically wishes his arms were free so he could touch himself.
"Uh-huh, for me too," Rin says, and Atsumu whimpers as he's fucked even harder. "Admit it Kiyo, it's because you want a go yourself, isn't it? You want to feel this human too."
Kiyoomi seems to ignore the comment, tapping a few more times on the interface.
“He’s close to orgasm,” he says after a moment, gaze flickering between both of them. “It seems your stimulations are working well.”
“Then m-make sure he gets there soon,” Rin pants, throbbing hard inside Atsumu. “I’m at my limit too.”
“Understood,” Kiyoomi says, and suddenly the vibrations on Atsumu’s nipples get way more intense. “Increasing stimulation to the nipples.”
The holographic interface flickers away as Kiyoomi moves closer, bending down to meet Atsumu's eyes. Atsumu blinks away tears, lost in pleasure and struggling to focus on Kiyoomi's face.
“Are you going to come, Atsumu?” Kiyoomi asks, and god the clinical way he's speaking is still unbearably hot. “We must gather your seed, so I need you to climax.”
“M-my cock,” Atsumu pants, cheek pressed to the table and moving back and forth as Rin fucks him. “Touch, touch it and I’ll come, fuck-”
“Oh,” Kiyoomi says, and Atsumu thinks he detects a hint of bashfulness as the alien’s eyes flicker to his groin and back. “Yes, of course. That makes sense.”
Kiyoomi stands, there’s some shuffling and a snap of latex, and then there’s pressure around his shaft. Atsumu shouts, pumping his hips into Kiyoomi’s grip and throwing them back to meet Rin’s thrusts. His orgasm settles at the base of his cock, only seconds away now.
“Is this good?” Kiyoomi asks, gently squeezing his hand around Atsumu’s cock, sloppy with leftover lube and his own fluids. “Are you coming?”
“Mmhm, fuck, yeah, yeah ‘m gonna,” Atsumu groans, feeling his balls draw up in preparation for what feels like the hardest orgasm he’s ever had. “Rin, faster, faster, please, god, fuck-”
“L-like this?” Rin asks, gripping Atsumu’s hips harder and slamming into him with renewed force. “I can’t hold it, I'm going to-”
“Yes, fuck, yes!” Atsumu shouts, biting his fist to muffle his cries as he starts to come. His cock kicks in Kiyoomi’s grip, shooting thick ropes of cum into the glass receptacle.
He hears and feels Rin go with him, a broken groan echoing in the room in time with the hot pulses filling his ass. Kiyoomi's other hand is gripping the table hard, knuckles flexing under the greenish grey skin. Atsumu wonders if they'd feel different to Rin's when inside him.
When Rin pulls out Atsumu just wants to collapse, his entire body shaking from the intensity of it all. But Rin's hand hold his hips in place, and Kiyoomi's dark gaze is fixed on his partner.
"You shouldn't deny yourself the pleasure, Kiyo," Rin says softly, gently plunging two fingers back into Atsumu and making his entire body jerk. "I got him all wet and ready for you, it would be rude to refuse."
Kiyoomi stands up, his breathing uneven and his hands flexing at his sides. His gloved hand is still dripping with lube and cum, and Atsumu can't stop staring at it.
"Besides," Rin continues with the tone of someone who's about to deal the finishing blow. "A bigger sample size means we can perform a larger variety of experiments, and be more thorough as well."
There's a beat of silence, the tension in the room so thick you could slice it with a knife. Atsumu holds his breath.
"You're right," Kiyoomi says quietly, and then he moves.
Rin's laugh bounces off the walls as the latex glove hits the floor and new hands grip Atsumu's hips. The sound of some fabric rustling is all the warning he gets before Kiyoomi lines himself up and pushes in and oh, he's bigger than Rin.
"Oh, stars," Kiyoomi breathes, and Atsumu swears he hears a suppressed whimper.
His trembling body is gently rustled as Kiyoomi starts to move, and Rin walks around to stand in front of him. His lab coat is buttoned again, and Atsumu can't help but feel a little disappointed. With gentle hands, Rin guides Atsumu up onto his elbows and cups his jaw to meet his eyes again, just like he did before everything went down.
"You see, Kiyo isn't one to let himself have pleasure too often," Rin says with a soft smile, stroking Atsumu's cheek with his long thumb. "I didn't want him to miss out on this excellent opportunity."
Kiyoomi's bitten-off sounds of pleasure are making Atsumu's cock twitch again, and he nods clumsily in Rin's grip. "'S okay, I like it, feels good."
Rin's smirk is sharp and lethal. "You hear that, Kiyo? Our human says you feel good. Shouldn't you return the compliment?"
For a moment, all Atsumu hears is the slap of their skin and Kiyoomi's ragged breathing. Then;
"He's perfect, so perfect, I-I… Rin, you know I won't last like this, not long enough for him to reach another orgasm."
"Oh, I know," Rin says, letting go of Atsumu's chin and moving to his side. "Which is why I'm going to help."
Atsumu's barely processed the words before Rin's hand grips his half-hard cock, stroking it slowly at first but gradually speeding up. Atsumu cries out, his nerves screaming with overstimulation, but Rin doesn't let up.
"I know you can do it, Atsumu," Rin purrs, and the holographic interface beeps again. "Your arousal is rising quickly, and we know exactly how to make you climax now."
The vibrations on his nipples start up again, and Atsumu's arms buckle for the second time tonight. His cheek hits the table again as he shouts his pleasure and pain into the room, but there's no doubt in him that the pleasure is winning. His hips jerk as Rin strokes him mercilessly, muttering filthy words of encouragement as Kiyoomi fucks him at an ever increasing pace.
"I'm gonna come again," Atsumu whimpers way too soon, stars dancing in front of his eyes. "Keep goin', don't stop, please don't stop, oh fuck-"
"Harder, Kiyo," Rin says, a little out of breath, and Kiyoomi complies with a stuttered groan. "That's it, just like that, he's so close now."
"I'm c-close too," Kiyoomi pants, and Atsumu kind of wants to listen to his beautifully broken voice forever. "Make him come, h-hurry Rin, I can't-"
Kiyoomi's cry of pleasure when he comes is so hot that it sends Atsumu straight over the edge, cursing loudly as his tender cock shoots into the receptacle yet again. Kiyoomi collapses over his back as he pulses inside Atsumu, shuddering and gripping Atsumu's body like a lifeline. It's strangely intimate, and Atsumu finds that he doesn't mind it.
When they've separated and caught their breath a little, Atsumu is released from the restraints. He doesn't move, just collapses further onto the table, closing his eyes to stop the room from spinning.
"He's fine," Rin says from over by the control panels, and Atsumu feels the ghost of a hand withdraw from the air above his cheek. "Just need to clean him up and confirm his vitals are staying stable."
Atsumu opens one eye just in time to see Kiyoomi turn away from him and start walking towards Rin, and his addled, filter-less brain makes his mouth say exactly what he's thinking.
"What, that's all ya got?"
Both the aliens freeze then slowly turn to look at him in almost perfect sync, which would be a little scary if it wasn't so funny. Unsurprisingly, Rin is the first to find his words.
"Are you saying… you want more?"
Atsumu shrugs as best as one can when laying down, a shit-eating grin spreading across his flushed face. "I dunno, just figured there'd be more freaky shit with aliens involved, y'know? Feels like I'm missing out."
Rin and Kiyoomi exchange a long, loaded look. Atsumu props his head up on his hand and bites his lip, breathlessly awaiting their decision.
"There's always the main research ship," Kiyoomi says, his gaze slowly drifting from Rin to Atsumu as he speaks. "We have some… quite interesting equipment there."
"Sounds like a party," Atsumu says, still grinning, heart pounding in his throat at the thought. "Am I invited?"
The room is quiet as Kiyoomi approaches him, curling his fingers under Atsumu's chin just like Rin. Atsumu's heart skips a beat and he finds himself lost in those deep, dark eyes.
"Whatever you desire, human."