Jim had Bones cornered. They'd been doing this dance for years now and Jim had finally gotten fed up with it. One day, after his shift had ended, he promptly stomped his way down (figuratively, of course, as Captains do not stomp anywhere on their own ship) the CMO's quarters and let himself inside. Unsurprisingly there was a very distinct lack of any kind of doctor in the empty quarters, but that suited Jim just fine. Without any further preemptive, he stripped out of his uniform straight into his skivvies and sat at Bones' desk to wait.
It was a little over an hour later before the doctor appeared. He had stayed in his office beyond his shift to finish up some annoyingly overdo paperwork. The day had been particularly uneventful and he had settled into the routine of mundane, so the shock of seeing a nearly nude man sitting at his desk was particularly fierce. He started and pressed himself against the just closed door of his quarters.
"Jim?!" he squeaked, most undignified, and stared in blatant shock. Jim just slowly turned in Bones' desk chair and looked up from the PADD he had been reading, all casual like. As if him sitting half-naked in people's desks was a common occurrence (for all Bones knew, it very well could be).
"Hello, Bones," he greeted and stood, a predatory look over coming his features. "Glad you decided to finally join me." He took a step forward.
Bones, who had stopped pressing himself against the door, felt the need to resume the position or perhaps just escape his quarters all together. He did not like the look in Jim's eyes one bit. It spoke of ill-gotten things between the sheets that Bones decidedly Did Not need from Jim, at all whatsoever no matter what his subconscious felt.
"These are my quarters," McCoy said, unnecessarily, feeling like he was really just grasping at straws now when the conversation had only just begun. "Could you leave and be naked somewhere else, please?"
The look on Jim's face only intensified at that and Bones regretted the words immediately. Jim took another step forward, slower this time, and settled his hands on his naked hips. "You'll be good to notice that I am not naked," Jim clarified, the 'yet' hanging implied between them—McCoy desperately resisted the urge to wave his hand through the air to shoo the monster away. "And I'd really rather be naked here than somewhere else, Bones—" Bones shuddered at the way Jim's lips agonizingly drew out the vowel sound in his dreadful nickname—"so why don't we make something of it?"
McCoy was really flailing now, feeling completely out of his element and all the more uncomfortable for it. Sure, he really loved Jim and hot damn, the man had the body dreams were made of, but he honestly hadn't had sex in a very long time. In fact, he was very much comfortable with this fact, having come to terms with it many a year ago, and rather liked that he had. He didn't want to give up the blissful stupidity of being free of sex because he knew, in a few years, when age gripped him that it wouldn't be something that came of bitter divorce but something that came of uncontrollable dysfunction.
"Alright," he said haltingly, holding up his hands to placate his best-friend-who-wanted-to-be-more. "Let's have a drink? I'll break out the good stuff."
Kirk was suddenly very close now and Bones did actually press himself back against the door this time. His arm shot up to slam against the door release but the firm grip on his wrist stopped the motion from reaching fulfillment. "No," Jim breathed, pulling Bones close to him and his near-nakedness. "We're not going to have drinks. We're going to have sex."
Bones winced at the dreaded 'S' word being dragged so violently kicking and screaming into the room with them. Jim noticed the reaction and smirked. "That's right, Bones," he continued, voice low and implying more about sex than his words ever could. "There's an elephant in the room and its name is sex. We've been doing this for years, denying this, but today I say fuck that because I want to fuck you."
"Damnit, Jim!" McCoy cried, yanking his arm free and stumbling away from Jim in the general vicinity of this closet. "I'm not having sex with you—"
"Why the hell not?" Jim demanded, intensity broaching from horny to angry very quickly. He just didn't get it, what was Bones' problem being so in denial like this? It just didn't make any sense. "Give me a goddamn good reason."
The doctor floundered before the answer was made clear right before him: he was a doctor, duh. "Sex… could kill you," he said, looking up at Jim with a crazed look in his eye. He raised a finger to point crookedly at Jim, jabbing it around to punctuate his every point. "Do you know what the human body goes through when you have sex?"
Jim was miraculously speechless, gaping at Bones.
"Pupils dilate, arteries constrict, core temperature rises, heart races, blood pressure skyrockets, respiration becomes rapid and shallow, the brain fires bursts of electrical impulses from nowhere to nowhere and secretions spit out of every gland, and the muscles tense and spasm like you're lifting three times your body weight," Bones continued without pausing once for breath.
"It's violent, it's ugly, and it's messy, and if God hadn't made it unbelievably fun… the human race would have died out eons ago," Jim finished, crossing his arms over his chest and looking thoroughly unamused. "Yes, I've seen that episode of House, iCameron/i. It's not going to work."
McCoy had been planning on annexing the last bit of the line but he was caught and had to admit it. He sighed and shrugged, looking resignedly at Jim. "Yes, alright," he tiredly said, conceding defeat. The gleeful expression that overcame Jim's features sent chills down his spine. Jim made a grab for him and, as quick as his old doctor legs would carry him, Bones scuttled away.
"BONES!" Jim bellowed after the shock had worn off. In the hall outside, a group of passing crewmembers paused all looking around in confusion for the source of the disembodied yell. "GET OUT OF THE GODDAMN CLOSET!"