It's already been a long day of meeting dignitaries from other planets when the Naarha leader approaches Keith carrying a small potted plant, something with yellow leaves and small red blooms. That isn't out of the ordinary; many of the aliens they've been meeting as the Coalition grows have brought gifts or tributes, wanting to do something to thank the Paladins of Voltron. After some early incidents that had nearly resulted in a couple of planets taking offense and leaving the Coalition, it had been decided that all gifts would be accepted with thanks.
Plants are a common offering, as are edible delicacies and ceremonial garb. Edible things are scanned for safety to humans, and the clothing is generally boxed up and sent away to be stored somewhere. Plants are most often sent to Colleen Holt, who is delighted to take any and all alien flora to add to her growing collection.
Normally, Keith would try to pay attention to the care instructions the delegate gives him, but it's been a long day, so he smiles and nods and they seem satisfied with that. By the time he makes it back to his quarters, he's got the plant, two different kinds of fruit, and something that he thinks is supposed to be art, but honestly just looks like a bright blue half-melted candle.
He sets it all down on the desk; he'll figure out what to do with it all tomorrow. He eyeballs his bed longingly, but he's supposed to meet Shiro in the gym for a workout and some sparring. He briefly considers cancelling, but he knows his exhaustion stems more from interacting with people all day than anything physical, and being around Shiro always helps him feel more centered.
Half an hour later, he has to admit he was right. They don't talk too much, taking up neighboring weight machines and settling into their regular workout routine. Just sharing the quiet space with Shiro has Keith feeling more like himself and less like… well, the dancing monkey the Coalition often needs him to be.
He's worked up a good sweat by the time he finishes on the machine, and Shiro tosses him a towel. "Feeling better?"
Keith quirks a wry grin at him as he mops the sweat off his face. "That obvious, huh?"
Shiro raises a shoulder in a shrug. "Probably not to everyone else. Rough day?"
"Not too terrible," Keith admits, trying not to think too much about how much he appreciates how easily Shiro can read him. "Just lots of schmoozing."
"Ooh, your favorite."
Keith scowls and throws his towel back at Shiro, who simply steps out of its way, grinning unapologetically. "Yeah, well. Not all of us can be as good at it as you."
"Just because I'm good at it doesn't mean I like it," Shiro points out. "But regardless, I'm sure you did fine."
"I don't know, maybe," Keith says dismissively. "Wanna spar?" Shiro's grin is answer enough, and they move to the mat.
There had been a time when Keith had been worried they'd never have this again. After the fight with the clone, Shiro had been hesitant to spar again, certain it would trigger terrifying flashbacks for Keith. Keith had insisted, though, and they'd eased back into it. There had been a couple of tense moments at first, but nothing dramatic. After all, trusting Shiro comes as easily to Keith as breathing.
Keith and Shiro are a lot more evenly matched now than they used to be, which in general is a good thing, but also means that Keith is now intimately familiar with how it feels to not only be pinned by Shiro, but also the sensation of pinning him. That's dangerous knowledge to have, a fact that he's reminded of as Shiro stares up at him in something like wide-eyed pride.
"Good move," Shiro says, grinning widely. "You'll have to show me that one later."
Keith laughs a little as he pushes himself up, extending a hand to help haul Shiro up off the mat. The move had been one he'd learned from his mom, definitely not Garrison standard. "I'm not sure you're flexible enough for that one, Shiro."
"I don't know, I might surprise you," Shiro shoots back, and well, what is Keith supposed to do with the mental images that conjures? He flushes red as he takes a step back, hand slipping from Shiro's firm grip.
"You have a habit of doing that, yeah," Keith agrees with a smile. "Ready to call it a night?"
"Who's the old timer now?" Shiro teases, grinning when Keith rolls his eyes. "You're right, though, we both have early mornings tomorrow. You're in that meeting at 0800, right?"
Keith groans. "Don't remind me."
"I'll bring coffee if you handle breakfast."
"You've got a deal."
When Keith gets back to his quarters, he takes a quick shower, purposefully keeping the water cooler than is strictly comfortable because he is not going to jerk off to his best friend tonight, not when he has to face him first thing in the morning. He's towelling off his hair when he steps back into the bedroom and sees the plant sitting on his desk. Is it his imagination, or does it look a little droopy?
Well, it wouldn't do to kill the thing before he can even get it to Colleen. All plants need water, right? He grabs the water bottle he keeps on his bedside table and tips a bit of water into the plant's soil; not too much, but hopefully enough to keep it til morning. The plant seems to perk up almost immediately, possibly even unnaturally fast, but Keith shrugs it off; alien plants are weird.
He sets his alarms for the morning and falls asleep quickly, damp hair curling on the pillow around him as he dreams of his spars with Shiro turning into something else entirely.
The next morning comes far too early, leaving Keith muzzy and bleary-eyed. It's a little unusual for him; he's usually good at waking quickly, but he's still dragging by the time he makes it to the meeting. He'd managed to remember breakfast, though, and happily exchanges a banana and granola bar for the cup of coffee Shiro offers him, with just the right amount of cream and sugar added.
"Mm, perfect," he sighs happily after the first sip. A moment later he opens his eyes to see Shiro peering at him worriedly.
"Are you okay?" he asks, frowning. "You seem a little… off."
Keith takes another swallow of coffee before answering. "I'm fine, just waking up slow today for some reason. This helps," he says, gesturing to the coffee. "Thanks." Shiro doesn't look convinced, but he takes his seat next to Keith and seems to focus as the meeting begins.
Which is, honestly, more than Keith can say for himself. He tries to focus, but by the time Allura is done introducing their guest presenter, some alien with a wide, football-shaped head, Keith has broken out in a sweat and is tugging at his uniform collar. His mind keeps wandering, and while it's not going anywhere it doesn't normally (seriously, the cut of Shiro's jaw over the collar of his uniform should be illegal), it is harder than normal to wrestle his focus back.
By the time the alien is droning on about advanced hydroponics designs, Keith's been hard for twenty minutes.
At first, he'd been so horrified by what was happening that he hadn't stopped to think about why. After all, sometimes it just happens (especially when Shiro's around, if he's being honest), but he can usually get it under control pretty quickly. Today that is most definitely not the case.
In fact, today it only seems to be getting worse. Not that he's getting harder, because that isn't physically possible at this point, but he's shifting in his chair, and barely able to restrain the gasps that threaten to escape at the sensation of his clothes shifting against his erection. He can't sit still, he wants to touch; he catches himself reaching for Shiro twice, and snatches his hand back each time.
Shiro isn't oblivious to Keith's discomfort, but Keith is desperately hoping he doesn't see the source of it. He's glanced over at him a couple of times with worried looks, but each time Keith has ignored it. Then he shifts once more, and he can't help it; a bolt of something like pain and pleasure all at once shoots up his spine, and his breath hitches in his throat, enough so that even Shiro hears it.
Shiro leans in close to speak in a whisper by Keith's ear. "What's going on? Are you okay?" His breath ghosts over Keith's ear and Keith shudders helplessly. There's no way to hide the motion, not with Shiro so close, and Shiro's look of concern somehow deepens. "Keith?"
"I…" The meeting has gone quiet now, as more people realize something's happening over on their side of the table. "I think something's wrong with me," Keith admits, curling in on himself, wrapping his arms around his waist in an effort to hide his predicament.
"Ok," Shiro says, his voice immediately soothing, taking charge of the situation. "I'm gonna get you to medical, alright?" Keith nods, his breath coming faster.
He's not sure exactly how they get to medical. He's hunched over, arms clasped around his middle, and Shiro is gently steering him, murmuring reassuring words despite the thread of worry in his tone. His hands are like brands on Keith; he swears he somehow gets harder every time Shiro so much as shifts the hand on his back.
He doesn't remember much about the tests they run, but he remembers whining when Shiro tried to step back from the table, and hating himself for it on some level. He's not like this, not needy and demanding, but Shiro takes it in stride.
"It's okay, Keith," he says. "I'm right here, not going anywhere."
At some point Coran gets called in to consult. The doctors have given Keith something in an injection that has helped a little, calmed his racing heart and bringing his erection down to maybe half-mast -- though they'd seemed shocked that it remained at all, given the amount of blood pressure meds they'd pumped into him. It's calmed him enough that he's able to focus on the grim set of Coran's mouth as he's talking to Shiro and the doctor on the other side of the glass window that faces the hallway.
Whatever he's saying, Shiro doesn't seem to be taking it well -- he turns white, then bright red, and Keith only has time to distantly wonder how bad it must be to get a reaction like that out of him before he's arguing with Coran, gesticulating, then running his fingers through his hair in frustration.
Keith's fingers twitch with the desire to replace Shiro's fingers with his own, to tug at his hair until he bends his head back, exposing his throat for Keith to leave biting kisses on, to--
Keith wrestles his mind back from that line of thinking in time to see Coran poking a finger into Shiro's chest, to see Shiro shaking his head. He looks genuinely distressed, something Keith never wants to be the cause of.
The men outside the room freeze when Keith speaks, Shiro looking in through the window with wide eyes. The doctor says something and Shiro hesitates, but shakes his head and replies. Coran reaches out and squeezes his shoulder before both he and the doctor turn, leaving Shiro alone in the hallway. Shiro takes a moment, seeming to gather himself, before coming into the room.
Keith watches as Shiro makes his way to the chair beside the bed, the smile on his face not reaching his eyes.
"How are you feeling?" Shiro's injecting a lot of calm into his voice, but Keith's known him long enough to see past that.
"I'm… okay," Keith settles on. "Better than earlier. I'll be even better when someone can tell me what's going on," he adds pointedly. Shiro's jaw clenches, his eyes dropping away from Keith's gaze, and Keith can't help but think about running his tongue over the sharp angle of that jaw. With some effort, he wrestles his mind back around to the conversation at hand, though he's aware on some level that he's getting harder again. "Look, I know it must be pretty bad if they're leaving you to tell me instead of the doctor," Keith says. "Just get it over with. Is it lethal?"
"No," Shiro says instantly. "God, no. Well," he amends, frowning, "not if it's treated." Keith nods, letting out a breath he hadn't realized he'd been holding.
"Okay, that's a start. What kind of treatment are we talking? I'm guessing it's something hard to get, considering how you're acting," Keith says. He shifts in the bed; he's starting to feel warm again, and it's getting harder to focus on the conversation.
Shiro's eyes snap to the bed as Keith starts shifting, and he flushes red. "It's not… hard to get," he says, pausing as if he's having to force the words out. "It's just unconventional, and… and there's some possible issues with it, so we--"
"Shiro," Keith snaps, "just spit it out." Shiro takes a deep breath and raises his gaze to meet Keith's.
"You have to have sex."
There's a long silence as Keith digests that. "I'm sorry, what?"
Shiro sighs. "The plant you were given yesterday? It's a ceremonial thing on their planet. It's never watered until the day of the owner's bonding ceremony, at which point it puts out a very potent aphrodisiac," he explains. "Coran and the doctor used a lot of fancy words, but what it comes down to is you have to have sex. Taking care of it by yourself won't cut it, and if you don't…" He hesitated. "Your blood pressure will skyrocket, and your heart won't be able to handle it. The amount of drugs it'd take to keep it lowered would kill you."
Keith's shifting uncomfortably in the bed again, struggling to follow the thread of what Shiro's saying, but he thinks he's got the gist of it.
"Okay," he says, gritting his teeth and trying to force himself to focus. "Okay. So. How do we find someone willing to fuck me without guilting them into it?" Shiro goes very still.
"Keith, you can't just… not with just anyone."
"Why not?" Keith demands.
"Because -- it's -- Keith, have you ever even done this before?"
"Been forced to fuck or die? No, that's a new one, but I'm not a virgin, if that's what you're asking," Keith forces out.
Shiro looks conflicted at that information, but he presses on. "Regardless, it should at least be with someone you trust, if not someone you care about," he says, frowning. "You might not be in full control of yourself, it can't just be some random person."
Keith huffs out a laugh, drawing his arms back around himself as a shudder wracks its way through his body. "Of course I'd rather be with y-you know, someone I know and trust. It's not that simple, though. Anyone I trust is a friend, and… and any friend is going to feel like they have to, once they know the circumstances," he says, stumbling and stuttering his way through the explanation, struggling to keep his focus. He can't take his eyes off of Shiro, off the way his adam's apple bobs as he swallows; he wants to nip at the skin there, then soothe the sting of it with his tongue, wants to see what noises that might drag out of Shiro.
"I need to go," Keith interrupts abruptly. It's all he can do to keep his hands fisted in his lap to keep from reaching out. "I know the problem, I know how to fix it. I'll deal with it. But I can't be here right now."
Shiro nods. "Yeah, okay. A hazmat team already removed the plant from your room, so it's safe to go back there."
Good, at least there he can collect his wits and figure out how to handle this. Keith staggers a little as he stands, and Shiro moves instinctively, hands out to help steady him. Keith's eyes widen in panic and he tries to sidestep him, but only manages to stumble more dramatically until Shiro's hands catch under his elbows. Keith's breath hisses out at the contact.
"Shiro, please, I can't," he says, his voice hoarse and broken.
"Let me help you," Shiro says, his face entirely too close.
Keith can't help but laugh, though it came out a little bitter. "Shiro you can't just arrange for someone to--"
"No," Shiro interrupts. "Let me be the one to help you." Even through the haze of arousal, Keith can see how much it costs Shiro to say that. His hands are a little too tight on Keith's elbows, his mouth set in a stubborn line.
"Shiro…" The name is almost punched out of Keith, an exhale of surprise and want that he can only hope Shiro is willing to write off as attributable to the plant's affects. Which it is. Somewhat. "You can't."
"Why?" Shiro demands. "I'm offering."
"And I'm saying no," Keith says stubbornly.
"Don't you trust me?" Shiro asks, trying to mask the hurt in his voice.
"Fuck, of course I do," Keith replies, sighing. "You know I do. But you can't do this."
"Why not? Let me--"
"I'm not a sword for you to fall on, Shiro," Keith snaps. Shiro goes very still at that, and Keith closes his eyes and tries to regain some measure of composure before he speaks again. "Please. Don't do this to us."
There's a long pause before Shiro finally nods.
"Okay," he agrees quietly. "But I'm at least going to help you back to your room. You can barely walk."
Every second of Shiro's hands on him is exquisite torture, but Keith knows he's right; he's shaky and his balance is all over the place. Keith tries his best to remain quiet, but about halfway there whimpers start escaping, causing Shiro's fingers on his hip to tighten. That really doesn't help matters, but he can't bring himself to say that, and besides, he needs the support; his legs are like rubber underneath him.
By the time they make it to Keith's room, he feels like he's a stiff breeze from coming in his pants.
"Almost there," Shiro says, trying to be encouraging as he palms the pad next to Keith's door. All Keith can focus on is the way his voice sounds, so quiet and low in his ear, and what it might sound like if he were encouraging him to do something a bit more fun.
Shiro helps him inside and deposits him on his bed, disappearing into the kitchenette for a moment before emerging with a cold bottled water.
"Drink this," he instructs. Keith does as he's told, lifting the bottle with shaking fingers. The cool water helps clear his head for a moment.
"Thanks," Keith says as he lowers the bottle, setting it on the bedside table. "Thanks for helping me get here. I'll be fine now, though."
Shiro hesitates, perching on the edge of the bed next to Keith. "I don't like leaving you like this. What are you going to do?"
Keith raises a shoulder in a shrug; he hasn't really thought that far ahead yet.
"I'll figure out something. Send out a few messages, make some calls. Surely I can find someone, right?" He means to lighten the mood a little, but his joke falls flat, and Shiro only looks pained. "I'll be fine," Keith assures him. "Really. You should go." Keith's hands are fisted in his lap, he's painfully hard, and Shiro is sitting far closer than it seemed like he had been just seconds ago.
Shiro hesitates, then reaches out, putting one hand over Keith's.
"Is the idea of it being me so terrible?" he asks. "It wouldn't -- I wouldn't let it change things, you know that."
Keith's eyes fall shut at the contact, and he bites his lip to hold back the moan that threatens to escape.
"Shiro," he says quietly. It comes out sounding like something between a curse and a plea. "You don't want this. Don't want me."
Shiro's hand tightens on Keith's for a moment. "Don't tell me what I want," he says, his voice suddenly sounding a little deeper, a little rougher than before. Keith opens his eyes in surprise and -- oh, when had Shiro gotten that close?
"I want to help. I want--"
He doesn't get any further, because Keith is crushing his mouth to Shiro's. He wastes no time easing into it, no hint of anything soft or chaste in his movements as he presses in hard, swinging a leg over Shiro's thighs to settle in his lap as he licks into his mouth. Shiro's hands settle on Keith's hips, gripping him tightly as if to keep him from slipping away, though leaving is the last thing on Keith's mind as he rolls his hips down into Shiro's. He groans at the contact, then buries his fingers in Shiro's hair, using the grip there to tilt his face to exactly where he wants him. He tilts him just far enough to the side to deepen the kiss even further, as if he can pour himself into Shiro, in and in and in and never stop.
He has to pull away to breathe eventually, though, so he simply uses his grip in Shiro's hair to pull back, tugging until Shiro's head tips back, exposing the long line of his throat to Keith's lips and tongue and teeth.
Somewhere around Shiro's adam's apple, something resembling coherency slips into the back of Keith's mind. Not enough to stop him, God no, nothing short of Shiro himself could do that now, but enough to send a spike of fear up his spine. This will ruin you, this will destroy everything you have with him.
"You should go," he says, panting. It's not as convincing as it could be, considering he can't make himself take his lips off Shiro's skin, even to speak. His voice is wrecked, but he can't bring himself to care. "Shiro, you--"
"Let me," Shiro replies, his hands sliding around to Keith's back, slipping under the hem of his shirt. "Please."
Keith's never been good at telling Shiro no, but he can be honest. He's good at that.
"If you stay, I'm going to fuck you," Keith says bluntly, pressing his hips forward again as if in warning.
The moan Shiro lets out at that is obscene.
"Yeah, yes," he agrees, hands scrambling to pull up Keith's shirt. He somehow manages to pull it off, even though Keith keeps trying to press as close as possible. It's an admirable goal, one Shiro is very much on board with once he's gotten both of their shirts off.
Once they're skin-to-skin, there's no going back. Keith rolls his hips down into Shiro's lap, groaning as he feels how hard Shiro already is for him. Keith runs his hands up Shiro's back, skimming them down his sides, then running fingers back up his abdomen, pinching his nipples on his way up. Shiro breaks the kiss, gasping at the sharp spike of pleasure-pain.
Keith's been turned on plenty of times before; hell, he's been turned on by Shiro plenty of times, but it's never been anything like this. It's never been this driving need, like he might combust if he doesn't get his hands on Shiro's skin, if he can't press against every inch of him.
For his part, Shiro seems on board with that plan; he's dropped his hands to Keith's ass, gripping tightly there and encouraging each roll of his hips, making hungry noises against Keith's mouth.
"Come on," Shiro says. Keith has no idea how much time has passed with them kissing, mouthing greedily at any skin they can reach, but Shiro's lips are swollen, red bite marks scattered down his neck and across his shoulders. It's a good look on him, Keith thinks distantly. He hopes he's able to remember it later; he wants it seared into his memory to keep him company later, when he can't have Shiro himself. "Keith, come on," Shiro repeats, fingers plucking impatiently at the button on the front of his pants.
"I thought I was the drugged one," Keith teases breathlessly, though he wastes no time in standing so he can pull his pants and underwear off in one move.
"Maybe there's still some in the air," Shiro says, watching Keith strip with darkened eyes. "Or maybe it's just you. I don't know." He reaches out, fingers skimming over Keith's lower belly, dipping lower, brushing through the dark trail of hair there.
The idea that Shiro might have been affected by the plant has Keith stepping back, worry flashing over his face. "Shiro, if you're affected--"
"Then it makes sense for us to help each other," Shiro finishes for him, a hint of warning in his tone. "Come on, come here," he says, reaching out.
Keith hesitates, but relents, gesturing at Shiro's pants. "Take those off first. I don't want to have to stop again." Pulling away from Shiro had been painful, and he didn't want to do it again. Shiro lifts his hips, eagerly shucking his pants and underwear, and Keith's mouth goes dry as he gets a good look at Shiro's cock as it springs free.
As soon as Shiro's pants are kicked aside, Keith is on him again, pressing him back into the bed this time. Shiro goes with the motion easily, reaching up to bury his hands in Keith's hair as they kiss each other hungrily.
A moment later, Keith groans loudly into Shiro's mouth as he feels a hand wrap around his cock.
"Shiro," he gasps, hips jerking as Shiro's hand twists skillfully.
"You've been hard for hours," Shiro says against Keith's lips, his voice low. "You need this. Come for me, baby."
That's all it takes, the combination of a few firm strokes and baby, and Keith is spilling over Shiro's hand and onto his stomach with a guttural cry, shaking as Shiro strokes him gently through it. He becomes over-sensitive quickly and reaches down to wrap trembling fingers around Shiro's wrist, halting his movement.
Keith comes down to the sensation of Shiro kissing his way along Keith's shoulders, lips soft, a hint of warm tongue leaving cool trails behind on his skin. He shudders and moves his hands to the mattress, pushing himself off of Shiro a bit.
"Okay?" Shiro asks, looking up at him. Keith takes a moment to consider before answering.
"Better," he decides. "Not fixed," he adds, wincing apologetically. He can already feel himself getting hard again. "But it took the edge off."
"Good," Shiro says. His grin is quick and sharp, and for a moment he looks like he couldn't possibly be a day older than he had been when they'd first met. "Because I recall you saying you were gonna fuck me."
Keith groans at that, and buries his face in the crook of Shiro's neck. He pulls back a minute later, looking down at Shiro seriously. "You want that? Not the other way around?"
"I want whatever you want," Shiro replies, and it should sound ridiculous, but his expression is so earnest Keith can't help but believe every word of it. "But I have to admit, that sounded pretty fucking good."
Keith sucks in a breath, then dives in to kiss Shiro again. Shiro meets him halfway, making a needy noise into the kiss that sets Keith's blood on fire.
"Yeah, it does sound good," Keith agrees when they break apart again. He's already fully hard again, almost dizzy with need. "I'll make it so good for you, Shiro, I swear."
"I know you will," Shiro agrees, leaning up to drop another kiss on his lips. "I want it, want you."
Keith doesn't know how to process that, much less reply to it, so he falls back on speaking with his actions instead, reaching out blindly to the bedside table, digging around in the drawer until he finds his bottle of lube. He sits back on his knees, and takes a moment to appreciate the sight of Shiro spread flushed and needy and wanton across Keith's bed. He runs one hand down Shiro's thigh and appreciates the shift of muscle there as Shiro lets his legs fall open.
Keith pours lube over his fingers, then reaches down, keeping his touch light, almost teasing over Shiro's skin, up the back of his thigh before dipping in to brush over his hole. He looks up to see Shiro watching him intently, and Keith meets his eyes as he presses one finger in.
Keith's driven hoverbikes off cliffs, he's piloted a number of impressive planes and spacecraft, and has bonded with and flown not one but two sentient lions, but in this moment he's pretty sure that none of those compare to the rush he feels as he watches Shiro's eyes flutter closed and knowing he did that.
Over the next few minutes, he adds another finger, then another, drawing sounds out of Shiro that he's only ever imagined in his most secret dreams. They're better in real life than anything he could have come up with. He scissors his fingers carefully, watching in awe as Shiro rocks back against his hand, practically fucking himself on Keith's fingers. In a moment of weakness, he leans down and mouths at Shiro's cock, humming happily as the salty flavor of the precome at the tip bursts over his tongue.
Shiro yells at that, arching up off the bed before pressing back down onto Keith's fingers, as if torn between which sensation he wants to chase more. Keith bobs his head a couple of times before Shiro's hand fists in his hair and tugs. Keith whines at the sharp pin-pricks of pain-pleasure, but Shiro continues tugging insistently while calling his name, so he lifts his head a moment later.
"If you keep that up, I'm going to come," Shiro says, breathing heavily as he looks down the line of his body at Keith.
"You say that like it's a bad thing," Keith says, pressing his fingers in and curling them in a way that makes Shiro gasp and shift against him.
"Keith," he says, the warning tone turning his name into something like a growl. The sound of it sends a shiver down Keith's spine. "I'd much rather come with your dick in me," Shiro adds, almost exasperated, and yet it's still somehow the sexiest thing Keith's ever heard in his life.
"How?" Keith asks without hesitation as he spreads lube over his erection with shaking fingers. "Knees, back, something else? Whatever you wa--"
"Just like this," Shiro says, reaching for Keith. "So I can see you." Keith, never able to deny Shiro anything, goes easily, bending over him to kiss him into the mattress. Shiro hooks his legs over Keith's hips, pressing his heels into the backs of Keith's thighs to pull him closer.
It takes every ounce of restraint Keith has not to plunge straight in; the need to fuck, claim, come burning in his blood, the fact that it's Shiro underneath him only adding fuel to that fire. The fact that it's Shiro also makes him fight that urge. He'd rather die than hurt him, even now.
He presses in slowly, every muscle in him trembling with restraint. Shiro is staring up at him, eyes wide, fingers clenching and unclenching on Keith's arms. Soon Keith is fully sheathed, chest heaving with deep breaths as he tries to control himself, tries to keep from coming immediately.
Shiro, however, is having none of that. He rolls his hips up, breathes Keith's name in something like a plea, and Keith responds immediately, setting in on a steady rhythm that he knows he won't be able to keep up for very long. It's hard and fast and primal in a way he's never experienced before, the drug in his system urging him on. Shiro certainly doesn't seem to mind; he's keening under Keith, urging him on, meeting every thrust with a roll of his hips.
"God, you feel so good," Keith groans, settling his hands at Shiro's hips. "Even better than I'd imagined."
"Yeah?" Shiro's metal hand runs down Keith's back, soothing and exhilarating all at once. His voice is breathless, but that doesn't stop him from grinning up at Keith. "You're amazing, baby. You're -- fuck, Keith," he gasps at a particularly sharp thrust. "I'm not going to last long," he warns.
Keith bends over without ever breaking pace to lick his way up Shiro's chest, then drops a biting kiss on his collarbone. Shiro jolts under him at the contact of teeth, but his hand finds its way to the back of Keith's head, encouraging him as he works on leaving a bruise that will be dark and visible for days. When he lifts his head, Shiro's waiting to seal their lips together, though that quickly devolved into them just panting into each other's mouths, unable to do much more than stay close as they each near the edge.
Keith can feel the end approaching, and can't do a damn thing to slow it down or draw it out, so he settles instead for bringing Shiro with him, reaching down to curl a hand around Shiro's cock.
Shiro's eyes fly open at that.
"Keith," he whines, and oh, Keith wishes he had that recorded. He'd listen to it every day. "I'm gonna--"
"Yes," Keith encourages him, moving his hand around Shiro in counterpoint to his thrusts. "Please, come, I wanna feel it."
That's all it takes. Shiro's thighs clench around Keith's hips as his eyes close, his mouth opening on a moan as he trembles, shaking apart as he spills over Keith's hand and his own chest. Keith barely has time to snap his hips forward twice more before he's tumbling over after him, groaning out something like Shiro's name as his vision whites out with the intensity of his orgasm.
The next thing Keith's aware of is gentle fingers combing through his hair. He's not sure exactly how much time has passed, but he's warm where he's lying on Shiro. He’s exhausted, but the burning under his skin has calmed, allowing him to think clearly for the first time in hours. He moves to sit up, hissing as all of his sore muscles scream in protest. Shiro's hand stills, then falls away, letting Keith sit up next to him on the bed.
There's a long silence as they settle next to each other on the bed, sitting up with what feels like a gaping chasm of space between them. The quiet feels like it lays heavy between them, not the comfortable silence Keith's used to them sharing. Dully, he wonders if this is what it will be like from now on.
"How do you feel?" Shiro finally asks. "Is it done, you think?"
"I'm--" He stops himself from saying he's fine, because that's not strictly true, is it? "It's done," he confirms. He's sore and tired and wants nothing more than to curl up next to Shiro in bed, but that's not the plant -- that's just Keith. Shiro nods, looking down at where his hands are clenched in his lap.
"That's… good," he says slowly. He hesitates, then adds, "Keith, I owe you an apology. I understand if you don't want to hear it, and I'll leave if you want me to, but God, I am so sorry."
"What?" Keith shakes his head, scowling. "I should be the one apologizing. What do you even have to be sorry for?"
"I didn't leave when you asked me to," Shiro explains, looking pained. "You were very clear about what you wanted, and I ignored that."
"You were affected by the plant," Keith says, waving off Shiro's apology without meeting his eyes. "Besides, you were right -- I probably wasn't gonna find anyone else."
"I'm not so sure I can blame the plant entirely… not for all of it, at least," Shiro says softly. He's looking over at Keith as if he's trying to convey something and can't figure out how to put it into words. "It may have… heightened things, a little," he says slowly. "But I didn't do anything I didn't already want to do."
Keith stares across at Shiro, utterly uncomprehending of what he's hearing. He can hear the words and theoretically understand them all individually, but all together they don't make any sense.
"You don't want me, though. Not like that. You were just helping me."
Shiro's laugh is quiet and self-deprecating.
"Keith, I've wanted you for longer than I care to admit. I never, ever meant to take advantage of you, though, and--"
"Shiro, shut up," Keith says, eyes wide. Shiro's jaw snaps shut in surprise, looking across at Keith. "You're telling me I've been pining after you for forever, I've been beating myself up over being in love with you, and I spent the last hour thinking you were going to hate me when we were done, and we could have been doing this all along?".
Shiro's mouth opens and closes silently for a moment before he answers.
"But you… you said brother."
"And you said nothing," Keith counters, pointing a finger across at Shiro.
"Well, I won't be making that mistake again," Shiro finally says, his expression settling into one of determination. "Keith, I love you, and I'd like to kiss you, plea--"
He doesn't get to finish his request before Keith is on him, pressing in close once more for another kiss, this one slow and warm and full of all the emotion he'd been afraid to show before. When they pull apart, Keith wrinkles his nose, looking down at their chests.
"We're kind of gross," he says apologetically. "We should probably shower. Probably somewhere else, so we don't get affected by the lingering stuff from the plant again," he adds.
Shiro's expression turns considering. "I don't know," he says, his lips turning up into a smirk. "It worked out alright the first time. I might not mind a little more."
Keith's grin is quick; he'd been thinking the same, though he hadn't been brave enough to admit it. "In that case, I'm happy to share my shower." He stands, offering Shiro a hand up. "Might be a squeeze, but I think we can make it work."
"Yeah," Shiro agrees, smiling bright enough to light up the room. "Yeah, I think we can."