Disclaimer - I do not own Star Trek or any of the affiliated characters.

The first time it hadn't been intentional, merely a hum beneath his breath during a physical as he allowed the tricorder to pass over the bare skin stretched taut against the back of one Chekov, Pavel Andreievich. It had been silent otherwise, barring the occasional blip from one of the various machines that littered the med bay and the deep breaths McCoy asked the teenager to take every so often to check the capacity of his lungs. And what a better way to remedy a deep-threaded silence – one that of which seemed to slip past professional and into the territory of uncomfortable – than by a gentle hum from no one other than the good doctor himself?

Only when the tricorder was removed from the proximity of his figure did Pavel dare to speak, to address the tune that flowed melodiously from within his attending physician. "Zat song... vhat is it? Ze vone you vere just humming now?" he questioned with a tilt of his head, curls bouncing the slightest bit at his forehead where they rested as he did so.

"What? Oh, hadn't even realised I'd been doin' it," McCoy commented offhandedly as he placed the tricorder aside and instead gathered a pen and Chekov's records into his hands. Mentally, he ticked off some of the more interesting notes in his head – seventeen years old, born in Russia, etc. At the bottom, in the medical section, he listed him to be fit as ever, as a seventeen-year-old junior officer should and would be. "S'a song I always heard my dad singin' – Daisy Bell. Real old song. Why?"

In response, the ensign simply smiled, offering a shrug of his shoulders and an explanative "I like it."

The comment left the Chief Medical Officer with a raised eyebrow and no words as he returned to scribbling down commentary in recollection of the physical. Once he looked up again, the teen sitting before him on the examination bed with legs swinging off of the side and shirt in his hands was absentmindedly gazing at the ceiling, a trace of the smile still playing upon his lips. And, though McCoy would never admit it, the smile reflected just barely upon his own face. Rather than acknowledge the tug at the corners of his lips, he dismissed the ensign, telling him that he would see him around the ship.

The second time, it may have been intentional on a subconscious level, but Bones wouldn't know because, damn it, he was a physician, not a psychologist. A familiar tune buzzed past his lips as he dabbed a damp, disinfectant-covered cloth over a cut on the forehead of the ensign, of Chekov. Hazel eyes watched as grey ones covered quickly with lids pressed tight in a squint, a wince of pain. Bones only ceased humming for a moment to chide him, saying, "I told ya it was gonna sting, kid."

"Pavel."

"What?" McCoy inquired, brows furrowing in confusion as he set aside the bloodied rag before looking once more at Chekov, who now had one eye opened cautiously and peering at him.

"Do not call me 'kid.' I have a name. Is 'Pavel.'"

"Well, Pavel," the CMO retorted, "I wouldn't call you a kid if you didn't act like one back there. The captain's going to put you on suspension from shore leave for the rest of your life!"

"Ze keptin vould not do zat to me, he is wery understanding," Chekov – Pavel – responded, sitting up just the slightest bit straighter, nodding in accordance with himself. This time, as he moved his head, the curls did not jostle around, instead remaining matted to his forehead with the blood that McCoy was attempting to clean. "Besides, ze keptin vill deal viz ze matter at hand. He vill give ze suspensions and lectures, not you," the teenager stated, puffing his chest out defiantly.

"Hey, kid—"

"Pavel."

"—kid, you oughta remember who your superior officer is!" McCoy snapped, watching as Pavel's resolve began to deflate, as did his stance. On the other side of med bay, he could hear Kirk lecturing the other ensigns involved in the incident. One of them, the ensign in the Engineering uniform currently passed out on a bed where Nurse Chapel read his vitals on a tricorder, had been playing a game of 3D chess with Chekov in the rec room when it began. The Russian whiz kid that he was now fixing with a glower had made a comment towards the other's loss that did go over too well. Other kid flipped the table, Pavel got lippy as he gathered the pieces, and soon the board was cracking over the seventeen-year-old's head, so on and so forth. Really, Bones didn't care – wasn't any of his business. What was, though, was the gash that hid in Pavel's hairline that just wouldn't let up on the blood.

"...I know, sir. I am sorry, sir."

With a sigh, the CMO felt his own resolve crumble at the apologetic look that filled the eyes gazing back at him from beneath long lashes. "Not a problem, ki—Pavel. Let's just get ya fixed up, okay?"

Both fell relatively silent after that, except for the constant stream of the Daisy Bell melody from the cantankerous doctor that seemed to soothe any rebellious feelings that stirred within the young man before him, Kirk still ordering ensigns around in the background of it all.

The third time, it was definitely intentional. Hell, it needed to be when the night ended with the kid a sobbing heap clinging to the front of his uniform.

It had been a few days after the incident of authoritative disrespect in the med bay, after things had quieted down with the lively group of ensigns, chess set replicated and forgotten. All of it began anew in the med bay, when the junior officer had shuffled in with his hands behind his back, toeing the ground nervously with his Star Fleet regulated boots as he asked Christine Chapel as to what the location of the grumpy doctor was. After being directed to the office in which the man sat, there was a set of two distinct yet hesitant knocks.

McCoy granted permission for him to enter, and when the kid did, he instantly regretted it. There, in front of him, stood the Russian, head still wound in bandages that suppressed some of his curls, the same apologetic expression marring his usually chipper face. Regret seemed to ebb off of the lithe figure in waves. Rolling his eyes – hopefully undetected by the one in front of him – Bones pushed his PADD aside, out of sight, out of mind. Instead, he fixed his attention on the teenager that now stood in his office, worrying at his lip with his teeth. Only when the doctor leaned forward expectantly did the navigator speak. "I haff to apologise again. Vhat I did vas wery disrespectful, as you are my senior officer, a good doktor, and a good man. I am sorry, Doktor McCoy." With that said, he lowered his head and awaited a response.

"Kid. Chekov. Pavel," he started slowly, wincing almost unnoticeably as the navigator's head snapped up in hopeful expectation. "It's fine. Just needed a drink the other night is all. So, really – it's nothin'." McCoy – Leonard – reached for his PADD again, expecting that the other would be satisfied with that response; he caught the crestfallen look on the golden-uniformed male's face as he raised the tablet up. Sighing once more, he let the PADD dip back down to his desk. "What? You look like I just kicked your puppy or somethin'."

"Is not okay! I vas extremely disrespectful, and I should be punished, as per regulations. I am wery sorry," Pavel retorted, seemingly bouncing anxiously in his spot.

"Whoa, calm down there, kid."

"Pavel."

"Pavel. Calm down. It's fine. We all get a little snarky sometimes." The doctor hoped this comment would be reassuring, rather than ruffling the kid more.

"Please, tell me vhat I can do to repay you," Pavel begged, tone exasperated, as if he were really tearing himself apart over a mere mishap with authority. His eyes were pleading, wanting something – anything – to redeem his poor behaviour with.

"Nothin'. It's fine," the reply came, an edgy tone to the voice it carried on.

"Zere has to be something!"

"Fine, fine! Here, you can repay me by getting out of my office!" McCoy barked, his patience being tested with the pleading child in front of him. And, in a flash, the kid was out the door, tearing through med bay. He could hear Chapel telling him to wait, asking what was wrong, if she could help, yadda yadda. Just let the kid go, Leonard thought to himself with a huff as he once more returned to his PADD.

Crash!

Only the words "damn it" passed through his mind as he rose from his seat, going into the med bay only to see Pavel and a few instruments clatter to the floor. Nurse Chapel was looking on from the side of a bed, hesitant and questioning as to whether she should help or not. With a dismissive glare, the physician sent her scuttling to her own office within the bay, only proceeding towards Chekov when he heard her door slide shut. At first, his steps were firm, long strides, but they slowed and hesitantly stopped when he heard something else.

Sniffling.

On the floor of his sickbay, he didn't have just a Star Fleet officer, just a navigator of a starship. No, he had a kid, a teenager with feelings that were visibly crushed, and for once, he didn't know what to do. So, proceeding with caution, Leonard approached the crumpled Russian, lifting him by the shoulders to collect him off of the floor. When Pavel put up a bit of a struggle, refusing to lift from the floor, the CMO let himself sink to his knees and hoist the teen up against himself. The other's thin figure fit comfortably in his arms as he sunk farther, leaning up against one of the frames of the beds. "Hey, kid, you're making a scene," McCoy commented, eyes taking a quick scan of the bay around them, which was thankfully deserted.

When all the doctor could discern from Chekov's response was "mmphvh," he pulled him the slightest bit away so the kid's face was no longer buried in his chest, dampening his uniform. The ensign kept his tear-stained face turned away, looking only when McCoy slipped a few fingers beneath his chin to force him to return his gaze. In the doctor's eyes, he saw the simple question of "what?" Repeating himself, he merely stated what he always did when McCoy called him "kid" – "Pavel."

Letting his fingers slip from beneath Pavel's chin, he placed his hand gingerly on the back of the other's curly, bandaged head, guiding it once more to his chest. "Pavel, calm down," the senior officer instructed, inhaling deeply as he cradled this Russian, this teenager to his chest. "It's okay. It's okay that you're sorry." As an afterthought, McCoy tacked on an apology for his own rather rude actions in dismissing him so unceremoniously from his office.

When he received no response, Leonard simply began to hum Daisy Bell until Chekov's own silence turned into soft snores, sitting on the floor in the middle of the USS Enterprise's med bay.

For the fourth time, it was due to the kid showing up at his quarters in the wee hours of the night, stating something about wondering if, perhaps, the good ol' doctor could pass him a glass of alcohol. When prompted about why he did not ask Mr. Scott, the navigator gave a small chuckle, commenting on the fact that the Chief Engineer slept like a log once he was out.

"Drinkin' is terrible for your liver, you know that," McCoy mumbled as he poured the kid a glass anyway. Chekov sat at the small table he kept in the corner of his quarters, toying with a loose thread on his standard-issue pyjamas. God, why was he even allowing the underage drinking to occur, let alone in his own domain? If asked later on, he would claim that it was because he was half-asleep.

After pouring his own glass, he joined Pavel at the table. Leonard was dressed in his own issued pyjamas – or at least partially. The top to the pyjamas was folded neatly at the end of his bed, where he preferred to keep it – said it was always too warm in his damn room to wear the thing, no matter what temperature he set his quarters at. So, with that in mind, he sat in just the bottoms, bare-chested and raising a glass of liquor to his face in parallel to Chekov, who did the same. With eyes trained on the teenager's face, the doctor expected at least a wince at the biting taste of the alcohol, but instead, he got nothing other than Chekov placing the glass down on the table once more and running the back of his hand across his pale lips. McCoy waited for the ensign to say something, anything, but nothing ever came. So, shifting a bit in his seat, he posed a question. "What'd ya need a drink for?"

At first, he was met with silence from Chekov, who was eyeing everything in the room with a curious expression on his young face. By now, the bandages had been removed, and the gash was altogether nothing more than a pallid scar in his hairline. Given the way it had healed, McCoy guessed the scar would fade in a few months time. It was once he raised a questioning eyebrow that Pavel spoke up. "I just have not been feeling right."

"How so? You need a check-up or somethin'? Could'a just came down to the bay," McCoy commented nonchalantly with a wave of his hand.

"Is not physical," Pavel murmured with a shrug, bringing the glass to his lips once more and taking a long sip. When the glass was returned to the table, his voice came back to him. "I zink I am... homesick."

Bones' face softened at that. He could sympathise with the kid, he really could. Hell, he was practically twice the other's age, and he still got homesick every so often. Sure, some of it was probably in part to his deep-rooted fear of space, but it wasn't all as such. Joanna was back there, back down on Earth. Granted, so was Jocelyn, which he could do without. Yet, regardless, he still longed for the sight, scent, and overall sensation of Georgia; he could bet it was the same with Chekov, yearning to once more see his family and the landscape of his homeland. The doctor was about to bite out that there was no hypospray for homesickness, but something inside him made him hold back, instead asking, "What was it like, Russia? Your family?"

The kid set off with a smile and a million stories, drinking away with Bones until he was no longer coherent enough to continue in his recollection of home. And when he stood to leave, he was also no longer capable of maintaining an upright position, slouching against the wall to catch himself with a stifled laugh. With no other choice – at least that was what Dr. McCoy was telling himself – he manoeuvred the junior office over to the bed and plunked him down, humming the mellifluous tune he had grown to realise soothed the nerves of the kid that was now tucked away in his bed, out like a light.

Returning to the table, the CMO sat himself down, finishing off his drink and dozing off in the chair.

The fifth, sixth, seventh, and eighth times all followed suit with the fourth, with the Russian whiz kid in his room, consuming alcohol until he couldn't even stand and was tucked away beneath the covers in his attending physician's Star Fleet regulated bed while the aforementioned doctor nodded off at the table, drink in hand.

The ninth time seemed to go in accordance with all of the others, but the night ended with a twist, something Leonard hadn't seen coming from a mile away, something that threw him off completely, what with the other nights of drinking becoming nearly routine. It was just three small words – and not the ones most would assume they would be – that left his head spinning and eyebrow raised so far on his forehead that it was surprising it didn't disappear into his hairline. "Sleep viz me."

McCoy's hands had stilled, blanket still gripped within them, now crinkled in white-knuckled fists. It was raised just above Pavel's shoulders, as per the usual height Leonard dared pull it to as he tucked the inebriated teenager in. "What?"

"You alvays sleep ower zere, alone. Zis is your bed, so you can sleep here too, da? Sleep viz me," Pavel slurred, looking up at McCoy with drunkenly glazed eyes, expression nothing but inviting and sincere. By now, the blanket was dropped upon him, draping over his thin figure, Leonard's hands kept to himself, one scratching nervously at his neck.

"Pavel," he started, now used to avoiding called the other a kid, as he knew how much it ruffled the other's feathers, "I can't do that. You're half my age, for the love of it all, and I'm your superior officer. Can't do it."

Whether the navigator wasn't listening or rather just did not care wasn't clear, but he lifted the blanket in a silent "shut up and lie down," smile dancing on his lips as his fuzzy mind cared not about any possible repercussions. "No vone vill know."

Leonard could only imagine what would happen if anyone did, especially that ridiculous captain he called his friend – he'd have a riot, that'd be for sure – or that green-blooded hobgoblin that followed Jim around like he was god or something. Illogical, was all the CMO could imagine the pointy-eared bastard saying in response if he discovered the possible ordeal – and good god, why was he even contemplating this? It was wrong. Wrong, wrong, wrong.

Then why did he find himself crawling under the covers beside Pavel, stilling as he felt the teenager cuddled up to his half-bare frame? Why did he find himself wrapping an uncertain arm around the warm body that the Russian possessed? Closing his eyes with a soft sigh? Humming the now commonplace, euphonic Daisy Bell as he buried his face in the navigator's curls?

Because it felt right.

The tenth time and nearly every time after that was when they were lying there, trying to recover from the breathless, sweaty panting that came with all of what they did. Each time, it was as the teenager's – teenager, for god's sake, McCoy always had running endlessly through his mind – naked body pressed eagerly towards his own clothes-less body, longing for cuddling in his post-coital bliss. Never did the CMO get used to this, the fact that he was twice this kid's age and yet there he was, bringing him again and again to his climax in the nights they had together. God, did he feel like a dirty old man, but damn it if he didn't enjoy it.

Pavel – Pasha, he had become accustomed to calling him now – always initiated it, ever the hormonal seventeen-year old, but McCoy always led it, experienced and a teacher for the teenager that climbed his body like a bloody pole. It seemed like the kid knew what he was doing, like he had a load of this at the academy, but Pasha had confessed to him that Leonard was his first and only – lord if that didn't make him feel like a pervert, taking the kid's virginity. But, lord if it didn't make him feel like he was shrouded in light, bestowed unto him by the heavens.

It always led to clothes being tossed hastily around the room, landing haphazardly all around. One time, the sexually frustrated teenager had whipped off McCoy's uniform top, chucking it behind himself only to have it land on and take down a bottle of alcohol, having it fall to the floor with a crash. To Leonard's recollection, if his memory served him right, Pasha actually broke down, began crying as he apologised profusely for destroying and wasting something that wasn't his, ever the apologetic little creature, but all the doctor did was press his lips to the other's, teeth clashing and hands roaming, mumbling something in between desperate kisses about it being fine, it's just alcohol, I can just replicate more, calm down. Needless to say, it was forgotten until morning.

Difficult, it was, to manage to hum the mollifying tune with all of the little moans and gasps Pavel made through each time littering his mind; regardless, he upheld his end of the routine, the susurrant melodia getting lost in Chekov's sweat-dampened curls as Leonard held him close.

It was that simple song that sent the exhausted teenager to sleep every night.

The last time, it broke his heart.

"Medical to the transporter room!" Kirk's voice had boomed over the conn, tone teaming with urgency and filling the whole of medbay with its commanding fullness. McCoy and Chapel had shared only a split-second glance with one another before rushing to the transporter room, only to see Scotty, Spock, and Kirk himself huddled around and blocking the view of the group of ensigns that had been sent down on the away mission. As always, the doctor expected it to be a red-shirt that he'd be cleaning up after, but this wasn't what he meant at all.

The shirt was red, all right – red, dampened with blood.

From beneath the carnage, he could see the gold tint of the uniform trying to peek through. Only then did he realise who the only Command officer to have went on the away mission was: Chekov.

"Daisy, Daisy..."

His heart was halfway into his stomach by the time he even reached the platform to gather the kid up in his arms. Kirk had lurched forward to help his friend pick up the ensign, but by the time he had done so, McCoy was halfway down the hall, Russian bouncing lifelessly in his arms with each pounding, vital step he took towards the sickbay.

"...give me your answer do."

"Help me out, here!" McCoy barked in command, gingerly setting down the unconscious navigator on one of the beds, sheets quickly staining with blood as the physician desperately felt around for a pulse in the thin, crimson-marred wrist that hung limply over the edge. Everyone was swarming him, his own staff, the transporter room posse, everyone trying to hand him tools and asking what they can do.

"Enough! Give him some room!" Kirk ordered, knowing Bones couldn't handle that many people surrounding him on a good day, let alone now. Despite being grateful, McCoy couldn't look away, not as he searched and searched and finally found a weak pulse of life threading through Chekov's pallid body. It was there, but just barely. Christine was running a tricorder over the small figure crumpled upon the bed, checking his vitals and for any possible infections in the wounds.

"I'm half crazy..."

The captain herded everyone unnecessary away from Bones and the commotion at the bed, shuttling them out of the room and setting himself and his trusty First Officer at the door to ensure that they remained in the hall. Scotty lingered unsurely by the two at the door, eyes looking anywhere and everywhere other than Chekov. The "wee little one" – as Montgomery called him – was one of his finest engineers, and the Russian didn't even work in that division. He was also one of his finest friends and drinking companions when he got the chance.

Ten CCs of this narcotic and fifty CCs of that narcotic were handed McCoy's way as he called out for them, injecting them all into the motionless body by means of hypo, trying to ease any pain that the other might have felt in his unconsciousness.

"...all for the love of you."

Barely even recognisable beneath of the blood, Pavel did not stir as Chapel tried to clean his face off, McCoy still examining and determining the extent of the damage: breath was soft, uneven, but still sustaining Chekov; shirt was torn across the chest, revealing a set of three large, to-the-bone gashes, akin to claw marks; the left sleeve was ripped jaggedly off, as was the arm that once filled it, nothing but a ragged, fleshy end jutting from the shoulder. It didn't look good.

With as little movement as possible, Bones had a few other of the on-duty nurses remove the uniform shirt and undershirt– what little was left of them, that was – as he gathered and readied the sterile bandages. When everyone and everything was cleared away, he began to wrap up the bloodied stump that was once an arm, needing to stop the bleeding.

"It won't be a stylish marriage..."

Next, the doctor moved on to the lacerations that tarnished Pavel's thin, barely rising chest. Why wasn't it coagulating? Why wasn't the damn blood coagulating?! Shaking his head furiously, the CMO utilised his supposedly magical, legendary hands in stitching up the wounds. As he did so, Nurse Chapel kept an eye on the vitals, frowning gravely at the uneven lines representing the ensign's heartbeat.

Every so often, Pavel would shudder beneath his hands, causing him to still lest he royally mess up the stitches and have to begin anew. They couldn't waste any time, not now, not with Pavel. No one understood what the kid meant to him, no one knew. This kid was his life now, whether he would admit it or not.

"...I can't afford a carriage."

And suddenly there was screaming, and at first, McCoy could't tell from who it came.

"But you'll look sweet..."

It was Pavel, wide-eyed and frightened, screaming like there's no tomorrow, heartbeat racing, wavering erratically on the EKG.

"...upon the seat..."

And right then, McCoy was pretty sure there isn't going to be a tomorrow, not for Chekov.

"...of a bicycle built for two..."

The physician's usually deft and skillful hands were scrambling, shaking as he reached for another hypo of narcotics, wanting to ease the pain for his Pasha. As he shot the contents into the navigator's neck, he caught the other's grey eyes, holding so much pain, so much fear, so much youth. He couldn't help it as he turned his own hazel eyes away, unable to hold the gaze that was bestowed upon him by the dying ensign before him. Pavel was bleeding out, and no matter what he did, nothing seemed to stop – it must have been internal, all the while he was worrying about the external injuries. God, he fucked up, and now Chekov was going to die because of it.

"...a bicycle built for two."

Despite the fact that he was shivering, covered in a sheen of cold sweat and blood, Pavel held his voice steady as he whispered, "I zink it is my time to go."

"God, Pasha," McCoy choked out, finally meeting the other's gaze again. It was horrible, heart-wrenching and just draining as he looked into the seventeen-year-old's eyes once more, slowly glazing over as more and more blood rushed out. In spite of it all, the Russian kept his fading gaze locked onto Leonard's own.

"Ya tebya lyublyu," Pavel murmured, voice nothing more than a whisper as the life continued to drain from him, hand weakly, blindly searching out Leonard's.

Grasping the seeking hand tightly in both of his own, bloodied from his attempts at saving his Pasha, Leonard tried his damnedest to keep it together as he replied, "I love you too, darlin'." When he noticed the dip on the monitor of the EKG, he knew there was nothing to do – nothing he could do – other than hum like he did any other time he wished to soothe Pavel's frayed nerves.

As he lie dying, just the slightest, nearly undetectable upturn at the corners of his lips let Leonard knew it was working, even as his heart slowed to a stop, EKG flat-lining as Pavel's body finally stilled.