Title: A Limb That Has But a Disease
Rating: PG-13
Pairing: Kirk/McCoy
Word Count: 4,370
Warnings: Mirrorverse, assassination attempts, hinted at torture
Summary: "Captain," Nurse Chapel says coolly. "You're needed in sickbay; it's Doctor McCoy."

A/N: For the Mirrorverse Remix Challenge at issenterprise. I was assigned the amazing and talented affectingly, and this story is a remix of her The Not-So-Common Cold. My immense gratitude to abigail89 for betaing, whipping this puppy into shape so it makes sense. :)

+++

Kirk's getting dressed when the comm in his quarters beeps, the flashing text indicating a call from sickbay. He accepts it with the slap of an open palm, plotting out the best way to teach McCoy a lesson about bothering him with non-emergency situations before he's on shift.

The voice that comes through, though, isn't in his Chief Physician's lethal drawl. "Captain," Nurse Chapel says coolly. "You're needed in sickbay; it's Doctor McCoy."

Normally a request like that would have Kirk sending Chapel off to the agony booths for a few hours, but Kirk's too busy running through scenarios to give it another thought. He straightens his vest then ties on the sash, making sure the agonizer and the knife are both on full display. "I'm on my way," he replies before terminating the connection.

There have already been two assassination attempts on McCoy; the first had been a lieutenant thinking he could use the doctor's death to get to Kirk. That bastard hadn't anticipated McCoy being perfectly able to take care of himself. The lieutenant found strung up on the catwalks in engineering by his intestines quickly dispelled the rumors that McCoy was under Kirk's protection.

The second had been one of the Gamma shift nurses. Doctor Lee had promised her Chapel's job once he was promoted. Neither of them got the positions they'd been hoping for, unless they'd also wanted to repaint the Enterprise's hull in faulty EV suits, which had actually been Chapel's idea. She knew that she wouldn't last if anything happened to McCoy, so Kirk trusts that whatever's going on, she's not the cause of it.

Sickbay is completely empty when he arrives. Kirk's hand automatically goes to the hilt of his knife, just in case. "Chapel?" His tone is more of a warning than a question, and almost automatically she's stepping out of a sectioned-off treatment area, coming to attention with a proper salute.

"Captain, Doctor McCoy has contracted an adenovirus."

Kirk can see why McCoy likes to keep Chapel around, the way she gets straight to business. He has no idea what this means, though, if it's lethal and highly contagious. He'd like to think McCoy wouldn't be separated from the rest of the room by just a curtain if that were the case, but why else would he be called to sickbay?

"It's a goddamn cold, Chapel, I'm fine," comes McCoy's voice, sounding a little thicker and even more irascible than usual.

Chapel steps back through the privacy curtain, and Kirk follows her. McCoy, he notices immediately, looks like shit.

"You look like shit, Bones," he says, at which McCoy scowls. And then promptly sneezes seven times, and while Kirk at least can't see anything with the tissues McCoy is clutching like a lifeline, it sure sounds juicy.

"She gave me a mild sedative." McCoy sounds like that's supposed to explain everything, but Kirk knows his appearance is due to the virus playing football with his immune system more than a drug that's supposed to calm him down. The way he's blinking slowly and having a hard time focusing, though, is making McCoy seem a little drunk, which Kirk knows is, in fact, the sedative at work.

"He can't be on duty, sir," Chapel begins to explain. "His immune system's compromised, so he can't be in sickbay, and he'll just get weaker as the virus runs its course. People on the ship are bound to notice, and some might try to take advantage of the opportunity."

Kirk doesn't need it spelled out for him that Chapel means anyone who might try to kill McCoy. Kirk's kind of curious as to what McCoy did to earn Chapel's loyalty so thoroughly, but he knows now isn't the time to find out. "You can't just give him the hypospray for it?"

McCoy snorts in annoyance, and Kirk can hear the snot moving around in his sinuses. "If this were caused by a rhinovirus or even a coronavirus, sure."

Crossing his arms in front of his chest, Kirk looks between McCoy and Chapel, waiting for further explanation. He feels like he's missing out on something here; his Chief Physician and Head Nurse are staring each other down like they're silently arguing over whether they're going to tell him or not.

"He's allergic to the anti-viral for this specific serotype," Chapel finally says.

And Kirk laughs. This is the man who is always mocking Kirk's own allergies, using them as leverage. McCoy is the only physician in the entire empire who knows that grocery list well enough to keep Kirk alive. The fucking is an additional perk.

"He has to stay in your quarters until he's better, Captain. I would estimate a week."

Kirk stops laughing, hand going to the agonizer at his waist for Chapel's insolence, and she tenses only slightly. Kirk slowly lowers his hand. He knows she's right. If McCoy has to be quarantined for the next week or so, his quarters are the safest; he's made sure they are himself. Too many previous captains had turned up dead in their own quarters at the hands of enterprising crew members. Pike had been the last on this ship, Kirk thinks, allowing the twist of a smirk to take over his face at the memory.

"Sickbay is yours until Doctor McCoy is well enough to reclaim his position," Kirk says, impressed that Chapel's face remains neutral with the news of her temporary promotion, despite the two other doctors on the Enterprise technically having seniority. But Kirk knows she can more than defend herself against anyone who would be offended, and she'll also gladly return to her normal post once McCoy is better. She's also smart enough to not thank him; he's definitely not doing her a favor.

McCoy has pushed himself into a sitting position on the biobed, feet hanging over the edge with his hands clenching the edge, eyes closed and jaw muscles tight. Kirk recognizes McCoy's reaction to vertigo all too familiarly, and he hopes the doctor isn't actually going to throw up. Kirk prefers dealing with bloodstains.

He grabs McCoy by the arm, forcing him to his feet, and Kirk feels better as he stumbles, feels more in charge here despite the fact that he's expected to play nursemaid to his Chief Physician. McCoy scowls, but there's no heat in his unfocused gaze. "Come on, Bones; we're having a slumber party."

Kirk's one step away from the turbolift when Chapel calls out from the entrance to sickbay, "If he dies, I'll kill you myself. Sir." The last she adds as an afterthought.

"I wouldn't expect anything less," Kirk responds with a cocky grin as the doors slide shut in front of him and McCoy.

Those they pass in the corridor either avert their gaze altogether after offering a salute or have a knowing smile on their face as Kirk drags McCoy back to his quarters. No one seems to suspect anything, and it helps that the sedative makes McCoy seem drunk.

"Someone did this," McCoy says in the turbolift, his voice filled with certainty. "I haven't treated anyone with an upper respiratory tract infection, and the sterilization fields kill anything external."

"You said yourself it's just a cold, Bones." The 'lift stops at Kirk's deck, and he drags McCoy out into the corridor. "There's healthy paranoia, and then there's whatever the hell you have."

Kirk keys in his code, enters then pushes McCoy onto his bed. McCoy falls onto the mattress with a relieved groan, which would normally be a welcome sound to Kirk's ears if it weren't for the rattling in his chest. Kirk finds a box of tissues to put on the bedside table and goes to replicate some tea in his small kitchen. Out of the corner of his eye, he sees McCoy stand and shuck off his uniform pants.

It's not because he cares, Kirk tells himself. It's survival for both of them to keep each other alive. It's not weakness when he asks for chamomile tea with honey and a drop of milk. Having his Chief Physician down for a week is bad enough; he can't afford to make the situation permanent should any of the crew find out. He thinks about those two assassination attempts, both not even three months into their first tour. It's been quiet for the last eight months now, but that doesn't mean no one's planning, waiting for an opportunity to present itself, an opportunity in the form of McCoy weakened by disease and unable to use the instant cure because of an allergy. And usually it's McCoy ranting about Kirk's own allergies.

Kirk brings the tea to the bedroom, stopping once he gets by the partition and can see McCoy on his bed, fast asleep. He'd managed to get his pants off, but he's still wearing his socks, and while he'd been able to undo the gold sash around his waist, that seems to be as far as McCoy could get. The sash is spread out behind him like a strange set of wings, the blue vest hanging open but still on. McCoy's snoring heavily, unable to breathe through his nose, and Kirk slowly approaches the bed, taking in the fevered flush of McCoy's skin, reaching out to brush the sweat-soaked bangs off the doctor's face.

McCoy huffs in his sleep and turns into Kirk's hand, which undoubtedly feels nice and cool against his face, but Kirk's pulling his hand back as if he's been burned. What the hell is he doing? He sets the tea down next to the box of tissues. He's supposed to have been on the bridge twenty minutes ago.

He leaves his quarters, making sure to put the highest level of security protection on them when he leaves. Not only does this ensure that he's the only one who can get in, but that McCoy can't get out, either, even if he were to comm Scotty and have the engineer beam him out. Not that Kirk thinks he would, but McCoy's known to get reckless when he's desperate.

No one asks where McCoy is; he has this shift off, anyway, but Kirk knows all he need do is make it sound like the doctor's being punished for something with a certain look in his eye and inappropriate hand gestures, and no one will think he's lying.

+

It's been three days, and after all of the sweating and phlegm, Kirk thinks he'll never be able to embarrass McCoy again. Although the watery eyes, red nose, and hoarse voice aren't doing anything to dissuade Kirk's dick, thank gods. Not that they've been fucking. McCoy can only wake up long enough to blow his nose or use the bathroom. And besides, Kirk doesn't want McCoy's mouth near any of his mucous membranes, thank you very much.

"How do you feel?" Kirk asks because it's safe. He's waited for McCoy to wake up on his own. The first time he'd woken the doctor up, he'd ended up with his own knife pressed against his throat, the one under his pillow, and they'd stared at each other, Kirk's eyes daring McCoy to make a move, until McCoy had remembered where he was and what had happened. He's still convinced he's been deliberately infected by someone with access to his medical files, but at least he doesn't believe that Kirk's the one that did it anymore.

McCoy takes a moment to inventory his symptoms. "Breathing's better," he says, and there is less of a rasping noise, now that he mentions it, but McCoy's voice still sounds fucked up. "I think I could eat." That's the most he'll say. He won't outright ask for anything from Kirk, and Kirk's not sure if he'd respond to a direct request. At least this way Kirk feels like he still has a choice in the matter, could deny McCoy anything just to make him suffer for a bit.

He replicates soup and juice, though, thinking over what he has to say next. His own curiosity had made Kirk look into McCoy's accusation that someone had infected him intentionally. "Only five percent of colds are caused by your particular virus," Kirk begins, looking over from the kitchen to see McCoy staring at him flatly.

"You don't think I know this?" McCoy's voice is muffled with congestion, their glaring at each other ending when McCoy wetly blows his nose.

"That means ninety five percent of colds have an anti-viral that you aren't allergic to," Kirk continues, thinking about all of the diseases being kept in stasis in McCoy's private lab. Some of these samples have long ago been eradicated on Terra, but McCoy likes to test them on new species, see how they react.

There's nothing quite like a pandemic to get a civilization to sign everything over to the Terran Empire if it means their people will be saved.

"I had Chapel run the virus in your system's genome against the samples in your lab. There was a match."

That straightens McCoy's posture a little as he moves to sit on Kirk's bed so his feet rest on the floor. "I'm the only one who can access the pathogens directly. The stasis containers can't even get a transporter lock on them."

No, Kirk realizes, but someone skilled enough might be able to get the transporter to ignore the container and lock onto the virus itself.

It wouldn't take a genius to then beam the virus into the bottle of bourbon McCoy keeps in his office. It's precision work, but Kirk thinks it's possible. Moving a virus over two rooms is easier in scale than beaming two people across space and into a ship traveling at maximum warp.

He puts the light meal on his small dining table, forcing McCoy to at least get his ass out of Kirk's bed because Kirk's not going to serve him or spoon feed him. The fever broke yesterday, so McCoy should be getting better now. Kirk's not going to treat him like an invalid, and even though McCoy scowls and complains, he seems to appreciate it. Or at least he's threatening Kirk's life less.

"I think you may be right, Bones," he says. "I need to check on some things, first."

It goes to show how poorly McCoy's feeling that he doesn't fight Kirk's short answer or insist that he can follow up on his own. He'd noticed that Kirk had locked him out of the ship's computer when he'd tried to access files through Kirk's personal terminal. McCoy is strapped to the bed as far as the crew knows, and Kirk can't have anyone noticing McCoy's accounts being accessed as long as he's stuck in Kirk's quarters.

McCoy opens his mouth like he's about to speak but is interrupted by a coughing fit, body wracking until his face turns red. Kirk doesn't realize that he's moved to stand behind McCoy, rubbing small circles in his back, until the coughing's over and they're staring at each other, McCoy's expression uncertain; Kirk doesn't even want to know what McCoy sees on his face.

He doesn't wait to find out, though, leaving his quarters without another word. He has to talk to Scotty, anyway, to find out who's been working longer on transport theory than they should be, and then figure out how he can get the fucker to expose himself.

+

"Ensign Adams," Scotty says without even needing to think about it. "Lass has been with us since the distress call from Vulcan, from what I know. The crew that have known her longer than I say she's changed, though - works more."

Get the fucker to expose herself, then, Kirk mentally amends. Kirk leaves engineering without another word, not wanting Scotty to learn too much. He likes the man and would be hard pressed to find a replacement should he have to kill him for getting too curious.

Kirk goes straight to the bridge, ignoring everyone's salutes as he goes straight for his ready room, having the computer bring up all information on Ensign Adams.

It seems that he misestimated that all crew from the Narada incident would keep their loyalties to the ship and, in turn, those they'd served with on that first voyage. Adams' husband had also been on that first crew, had been injured in the battle, and he'd died in sickbay. It's easy to draw the conclusion that she blames McCoy, the physician in charge, who had been operating on Captain Pike for hours instead of just letting him die. Kirk knows that it had been for his benefit that McCoy saved Pike's life. Kirk wouldn't have had the satisfaction of killing Pike himself if he'd died from Nero's hands or his injuries.

He returns to his quarters, telling himself that he just wants to tell McCoy what he's learned, not that he's checking in on him, only to discover that something's wrong before he even starts entering his door code. The small, red light that signifies the highest security level's been set isn't on, and he lashes out, kicking the door, before entering his usual code to gain entry. Kirk had left in a hurry earlier, had been too caught up in that moment of weakness to remember to set the security system.

McCoy is gone.

"Computer, what is the location of Doctor McCoy?"

"Deck 3, section 4, recreation room 3."

Kirk's been in the Imperial Fleet for a long time, since before his actual enlistment, and he'd heard stories from his mother, but he'd also heard ones from his uncle that they both knew Winona wouldn't want her younger son to hear. He's since spent his time in the rec room on both ends and knows that they're used when you need somewhere soundproof and don't want to be recorded by the security feeds.

He only keeps himself from running because he doesn't want any crew that he sees to know about the blinding rage he's feeling at just the thought of McCoy being harmed.

Kirk arrives in time to see a tall woman with dark hair pulling a hypospray away from McCoy's neck; the doctor falls to the ground awkwardly, having been kneeling with his ankles bound and his wrists tied behind his back. Kirk rushes at her, grabbing her hand with the hypo with his left hand and wrapping his right around her neck, and slams her backwards into the wall. "What did you give him?"

She's nearly his height, and Kirk can see that her pale gray eyes are dead. Adams doesn't even try to struggle against him. "Just helping him get over that nasty viral infection, Captain." She studies him for a moment, and Kirk's reminded of those fucking creepy Betazoids with their mind reading. "You'll know how I feel when you lose him."

Kirk squeezes the hand at her throat a little tighter. "Shut. Up."

"You love him," she gasps, and Kirk can't deny it because it's true, it's so true, and he's condemned them both for it.

He spots one of the manacles hanging from the wall and releases her neck to cuff her left hand, pulling the chain so her feet are just barely off the ground. Adams has to drop the hypospray and hold the chain with her other hand to keep her own weight from dislocating her shoulder or breaking the bones in her wrist and hand.

The choking sounds bring his attention back to McCoy. His face looks puffy and he's gasping for air. Kirk had looked up the specific reaction, knows that McCoy's blood pressure is dropping, which will lead to shock and then death. He doesn't know how much time McCoy has, but Kirk doubts it's enough for him to carry the doctor up to sickbay. "Kirk to Chapel."

"Captain."

"Doctor McCoy is having an allergic reaction to the adenovirus anti-viral at my location. Get down here, now!" Kirk disconnects before Chapel can affirm or deny the order. If she doesn't show up in time, Adams will be having company.

"You better hope he doesn't love you too," Adams says too casually for someone who's strung up and soon to be facing the worst pain Kirk is capable of inflicting.

"I do," Kirk responds with a snort, appreciating the irony of his words, the morbid way they fit the situation. It's an art form amongst the Imperial Fleet's officers to find each other's weaknesses and exploit them. Adams and her husband were lower ranking, wouldn't have attracted anyone's attention, but the two highest officers on the fleet's flagship are something else entirely.

Chapel arrives with the hypospray, and Kirk doesn't even question its contents before the drugs are being unloaded into McCoy's system. He inhales like someone had been holding him underwater, and even though the swelling hasn't started to subside yet, McCoy's airways sound clearer.

"Help him to his quarters," Kirk commands. It's the best option now with the security of his compromised, and Kirk doubts Adams is working alone.

"Yes, Captain," Chapel responds quickly, but she hesitates next to McCoy like she doesn't know if she's allowed to help him up or not. McCoy waves her away, standing on his own with a wheezing cough, and while Kirk doesn't know how far he'll be able to make it, McCoy at least walks out of the rec room on his own.

When the door slides shut, Kirk turns back to Adams with a hard gaze, and he knows it's going to be fun when she doesn't even wince.

+

Kirk still has Adams' blood, dry and crusty, beneath his fingernails when he arrives at McCoy's quarters. It's mostly dark, and McCoy is asleep on his side, head elevated by his pillow, which has been folded in half. He doesn't wake up when Kirk walks across the room or when he sits on the edge of the bed, frowning as he studies McCoy's sleeping face.

He tries to think of when it might have happened, when mild animosity became grudging respect, which then led to something that Kirk knows he feels but he won't say, not ever. He's the captain of the empire's flagship - he's not allowed to have weaknesses. The emperor would order Kirk to be executed if word gets out. McCoy, too, even if it's unrequited.

Kirk reaches forward, brushing aside the hair that's hanging over McCoy's forehead. "To cut it off, to cure it, easy," Kirk whispers, all too aware of the weight of the knife hanging from his sash. He could be done with McCoy now, could make it look like an assassination attempt and blame the people who had been working with Adams (Kirk knows who they all are - she gave them up eventually), or he could even blame Chapel, the last one to see McCoy alive. But then Kirk would be down two trustworthy medical personnel, and their knowledge about his physiological weaknesses. Even in the face of what they might know about his emotional one, it's too important to risk.

"Bones, Bones, Bones. What am I going to do with you?"

"You could let me sleep, asshole," comes McCoy's rough voice as he tilts his head up to glare at Kirk, but the effect is lost with his eyes all glossy and unfocused. He sits up, sheets pooling at his waist. "Whose blood is that?"

"Your dear friend Ensign Adams'. She's in a booth overnight, but I thought I'd save the honor of killing her for you."

"You didn't just do it yourself? It's only my life she's threatening; it's your reputation." McCoy says it so nonchalantly that Kirk almost misses the implication.

McCoy knows.

"I was there. Could barely hear over the blood roaring in my own ears, but that was hard to miss." McCoy's eyes look too bright as he studies Kirk. "What are you going to do about Adams?"

Kirk can handle anger right now, so he takes the opening. "Keelhaul her with the rest of them during Alpha shift tomorrow. I won't know who they've spread the information to, but it should keep the smart ones from opening their mouths."

"I know too, Jim," McCoy replies, looking more through Kirk than at him, but it's the use of his first name that has Kirk's thoughts stuttering. It's hard to tell the tone he's projecting with the way McCoy's voice sounds like he has rocks in his throat, both from the coughing and the allergic reaction, but Kirk thinks even then he should still be able to pick up loathing and disgust.

So Kirk leans in and kisses him, all teeth and bruising force, because nothing has changed, not really, and he needs McCoy to see that they can go on like things are normal, like things are the same as they always had been. Because Kirk can't kill this man, he realizes. He'll kill all the rest of them before he'll kill McCoy, and even then he will probably take his own life first.

McCoy pulls away to cough into his shoulder, body spasming and shuddering and not in the way Kirk prefers, with McCoy flushed pink from pleasure instead of sickness, but it strikes him how similar of an effect both have on the body, lust and disease. Kirk places his hands on McCoy's shoulders, easing him back so he's lying down on his bed again.

"You rest," he says, intending to put more of a commanding edge in his voice that seems to be eluding him at the moment. "Can't clear you for duty unless you're at one hundred percent. Need to make sure you can defend yourself."

"And in the meantime?" McCoy asks, raising an eyebrow at Kirk.

"In the meantime, your Head Nurse will see me dead if I don't bring you back in one piece."

"Piss poor job you've been doing so far between Adams and my immune system," McCoy huffs as he rolls onto his side.

Kirk opens his mouth to respond but is interrupted by the rattle of McCoy's snoring. "I'm going to take care of you," Kirk says, running his hand down McCoy's back before rising from the bed to replicate something to eat.