It had been, as far as away missions go, a pretty boring plan.

A straight-forward recognizance mission to an uninhabited planet, more of a field trip than anything else, and a favor to Sulu. Readings from the surface show signs of a large plant, similar to the terrain aloe plant, something missing from the botany bay Sulu has been cultivating on Deck 9. Having finished mapping the surface early, and with nowhere to go before a rendezvous with a supply freighter a few days later, Kirk had authorized an away mission to check it out. Chekov had immediately volunteered as Sulu's assistant, and McCoy had surprised everyone by volunteering as the medical liaison. He had grumbled something about the plant probably turning out to be poisonous – "because we all know a mission can't end without me having to hypo someone" – but really, the thought of planting his feet on a surface that was even slightly earth-like was too tantalizing to resist.

As for Kirk, well, they all knew the captain was physically incapable of resisting an away mission, no matter how much Spock cited regulation from the door of the transporter room.

"Captain, while the planet shows no signs of intelligent life, the cyclical ion storms will make it difficult, if not impossible, to reach you for several hours every night."

"So you told me, Spock. That's why we're bringing these." Kirk pats the packs on the pad behind them, full of the equipment needed to stay overnight on the planet.

"For a captain to be unreachable because of a completely unnecessary mission -"

"Spock! There's no one around, up here or down there. I'm going. You're gonna get to sit in the chair, Sulu's gonna get a new plant, and I'm gonna get to go camping. It's gonna be awesome."

Spock cants his head to the side in what McCoy had come to recognize as a Vulcan eye-roll, then glares at McCoy. McCoy just gives a shrug, and grins.

Defeated, Spock gives the order to energize.

The planet is as beautiful as promised, and after declaring the aloe-like plant safe – "nope, not gonna eat you, or spit at you, or poison your blood," he tells Sulu cheerfully, who all but gasps and whips out his equipment, Chekov scurrying close behind – he has laid himself down on the grass (well, whatever passed for grass in outer space) and allowed himself to imagine he was back in Georgia.

His peace is interrupted by Kirk rattling around, setting up the tents. Judging from the quiet cursing, they are not nearly as self-inflating as the packaging had promised. When Jim curses in pain, McCoy gets up and pokes his head in the tent.

"What the hell are you doing in here?"

Jim frowns, and sucks on a finger. "I pinched it on the poles. Because we can get a ship to travel at warp but we still can't get a tent that sets up without injuring someone."

McCoy chuckles, and takes Kirk's hand to survey the damage. The skin is red from the pinch but otherwise fine. Bones kisses it. "There. All better."

Jim's grin is lecherous. "You should do that every time I hurt myself."

Bones rolls his eyes. "Sick bay doesn't need that kind of show."

"You know," Jim slides up closer, practically into McCoy's lap. "Sulu and Chekov are out collecting samples and won't be back for a while. We could…test out the sleeping mats."

McCoy hesitates just long enough for Kirk to take advantage and kiss him, slow and deep, and Bones finds himself responding.

"Sulu to Kirk. Come in, Captain."

"Oh for the love of -" Jim flips open his comm. "Kirk here. Everything all right?"

"Yes, sir, but we're going to need some extra help getting all these samples back to camp."

McCoy huffs, and Kirk grins at his annoyance. Later, he mouths. "Understood, Lieutenant. On our way."

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Except by the time they haul all the samples back, and cook dinner, and listen to Chekov's excited but very long explanation as to why the ion storms come only at night – "it is the four moons, keptin, the way they rotate in overlapping and non-elliptical orbits" - McCoy is so tired he can barely keep his eyes open, and it's Jim's turn to huff when Bones slaps his hand away and falls straight asleep.

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

McCoy's been a doctor too long to not have developed the ability to wake up, fully aware, at the slightest provocation. So when his subconscious hears something that sounds like a pained moan, he's immediately sitting up and looking for the source.

But it's quiet, save for Jim's steady breathing and a slight wind outside, so Bones relaxes back down.

And then he hears it again. Except it's not a pained moan, per se, so much as…

"Shhhh, Pavel. The captain and doctor are right there."

McCoy's eyes widen.

They can't be serious.

The rustling of the sleeping bags and sounds of wet kisses convinces Bones they are, in fact, serious. When one of them, well, it's slightly more manly than a giggle, but not quite – when one of them giggles Bones finds himself reaching over towards Jim, because there's no way he's going to be the only one awake for this. He gives the sleeping man a sharp shake to his shoulder, then clamps his hand over Jim's mouth before he can protest the treatment. Jim struggles for a second before he realizes it's just Bones.

McCoy puts a finger to his lips – be quiet – and taps below his ear. Listen.

Jim glares at him through sleep-heavy lids and pulls McCoy's hand off his mouth. He looks as if he about to complain when there's a sharp gasp and a Russian-accented oh, yes from the tent next door. Kirk's eyes snap open, and Bones has to suppress a snicker.

Jim stares at Bones as they both listen for a minute to the rustling and sighs. Are they – Kirk mouths, and makes a crude gesture with his hands.

Bones shrugs, and leans in until his lips are almost against Jim's ear. "They're doing something," he whispers.

The look on Jim's face is a mix of surprise and glee and maybe a little bit – a lot of bit – of pride. He and McCoy scoot as close they can to edge of the tent as silently as they can, all but pressing their ears up to the side. It's not terribly comfortable, McCoy lying on his stomach, pushed up on his elbows, Jim hanging over his lower back, but it doesn't shake their focus. They don't catch everything, try as they might, just snippets of conversation in between moans and kissing sounds.

"Oh God right there -"

"I need -"

"But we don't have -"

A wet kiss, then a zipper pulls, and there's a chuckle.

"Why, Hikaru." Chekov's voice is impossibly deep and Jim and Bones both freeze. "You naughty boy."

There's no air in the tent for a few seconds as they both suck in shocked breaths at the same time. Then Jim lets it out, slow, and whispers, just barely audible, "damn, Ensign."

Bones loses it.

He doesn't mean to laugh, but it's just too much, the entire scenario: the captain and chief medical officer of the Federation's flagship, listening in as their best pilot gets seduced by an 18-year-old ensign who still pinks up when a girl sits too close next to him but apparently turns into, well, Jim Kirk when left alone with Hikaru Sulu. McCoy's whole body shakes under the strain of keeping quiet, his breath coming in short huffs out his nose.

Jim glares.

Bones is trying to stop, he really is, and he's almost there when Kirk leans down and hisses right into his ear, "damn it, man, get yourself together," and Bones loses it all over because damn it, that's his line, and Jim stole it. He buries himself under Jim, face in the blankets, tears streaming down his face because this has to be one of the most absurd situations he's ever been in, and with a best friend like Jim, he's been in a lot. He can feel Jim's chest vibrating above him as Kirk tries to keep in his own laughter, his face pressed into McCoy's neck.

Then Sulu gasps out a fuck, yes and Chekov mutters something in Russian that McCoy just instinctually knows means something filthy before switching to English just in time for –

"So tight, Hikaru."

McCoy blinks.

Well, that seals it. He's been all around the galaxy but right here, in a tent on some backwater jungle planet, he can finally say he's heard it all.

He turns slowly to hazard a glance at Kirk, whose face has gone completely slack. Then his face splits into the most shit-eating grin McCoy has ever seen.

Chekov tops, he mouths and even without sound Bones can hear the unbelieving tone. McCoy can't quite believe it himself.

Jim's got this dreamy, satisfied look as on his face as he lies down so his chin is resting on McCoy's shoulder, his mouth near his ear. "This is perhaps the greatest knowledge anyone could have ever given me," he whispers. "Bones, I'm so proud of our little Pavel." McCoy rolls his eyes but puts Jim's hand affectionately, like an indulgent parent.

There's a muffled cry – "think he shoved his face in the pillow?" Kirk murmurs, and McCoy elbows him in the gut – and a moan and the sound of a body slumping against synthetic fabric. It's followed by a few whispered works, and some heavy breathing that eventually slows out, and Bones and Jim realize they are listening in the dark to two men sleeping.

"Well, that was…" Bones searches for the right word.

"Hot?" Jim supplies in a low voice.

Bones starts to mock him but can't bring himself to do it because, well, it kind of was.

"Hey, Bones?" McCoy suddenly becomes aware that Kirk is still pressed up tight against him and his voice has taken on that tone.

"No," he says immediately.

"Oh, come on." Jim slithers up with more grace than any grown man should possess to lie on top of Bones, and cants his hips forward just slightly. Bones feels his breath catch but sets his face firmly in disapproval.

"No, you pervert."

Kirk makes an innocent face, as if to say, pervert? Me? "I'm not the one who woke up his sleeping captain to listen in," he points out.

"Only because I wasn't going to be – shit, Jim, stop moving your hips – I wasn't going to be the only one suffering through it."

"Bones." Jim snakes a hand down and palms the hardness he finds there and McCoy can't help but press into it. "I find it hard to believe 'suffering' is what you were feeling."

"Damn it, Jim," he hisses. Grabs Jim by the back of his neck and yanks him down for a hard kiss. "You… you…sexual deviant."

Bones feels the chuckle against his lips. "Smile when you call me that," Jim murmurs, and licks his way into McCoy's mouth at the same time he slips his hand under the loose sleep pants and squeezes. Bones whimpers, and Kirk chuckles again.

"Quiet, Bones. You wouldn't want to wake up our neighbors."