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Let me Be Your Dog

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"Jim —!"

Christine startled awake at Leonard's cry from the adjoining room, but she couldn't move, limbs heavy with whatever sedative was still running through her veins. Furious, effectively pinned by her own weight against the familiar texture of her own bedding, unable even to lift her eyelids, she listened.

"Fuck — Christ — Bones!"

The captain's inexplicable nickname for McCoy; the captain's voice, gone husky and sharp. And the rhythmic slap of body on body, telling her exactly what they were up to — what she couldn't tell was whether McCoy was a willing participant.

She strained to hear every noise they made: trying to interpret his well-being by the sound of grunting breaths and the struggle of skin against skin alone. Little by little, the fire of her protective anger burned away the heavy paralysis. Her eyes slid open slowly and she forced one forearm beneath her, bracing to flip over onto her back by willpower alone.

McCoy had better be willing. The last thing Christine wanted was to have to kill Captain Kirk for breaking her doctor.

Finally, McCoy growled: "God, yes. Move, dammit."

She snarled. Okay, fine. Enjoying himself, and from the low moan that broke over the last word, the captain wasn't objecting to taking orders. Interesting.

She realized she wasn't really surprised at what was going on in McCoy's inner room. She'd've had to be blind to have missed Kirk's interest during his visits to Sickbay, though as far as she knew — and she would know — they'd never acted on it before. And while she was aware that McCoy was lonely, touch-deprived, unwilling to risk intimacy with anyone on the Enterprise's crew — and had repeatedly let her enforce that decision — no one else on the ship had ever made McCoy blush.

Christine twisted angrily on the bed, feeling returning to her numb limbs, skirt riding up over her tingling thighs. The ceiling started to come into focus, and she wondered which of them she was going to end up murdering over the sedative hypo. She placed her hands on the bed, and used her ire as impetus to push herself to a sitting position.

The door between her quarters and McCoy's stood open; someone had told the computer to keep it that way. But the tiny red "lock" indicator glowed next to the door to the corridor.

Kirk yelped, then laughed. "Oh, that's cheating, you sly Southern asshole."

"Just because I can't hurt you don't mean I have to play fair."

Her boots were still on; the leather warm on her calves, custom-molded soles protecting her from the bare metal floor. In fact, all of her clothes were still on. No murder, then. A maiming would be sufficient. She tried to get up from the bed and ended up kneeling — but not prone — next to it.

The rhythmic slapping slowed, then paused.

"God damn it, Jim, move."

"Oh, no," Kirk said breathlessly while she pulled herself to her feet and checked her scabbard — empty, naturally. "I like you right where you are, Doctor. Right on the edge. Begging."

The jeweled stiletto she used as a hairpin was missing, too, her blonde hair loose around her neck and shoulders. This time, when she tried to rise, her legs held.

McCoy gave a keening whimper that sent a tickle through her clit.

"So you liked that, then?"

Christine gritted her teeth. She'd dreamed, occasionally, of drawing such noises out of McCoy's throat. She knew — they both knew — too many reasons why allowing sex into their interdependent relationship would be foolish, even dangerous. But practicality never stopped a woman from dreaming.

She made her unsteady way to the door between their rooms, listening to McCoy murmur some response too low to make out, wondering what exactly Kirk was playing at.

This was no crime of passion, no random impulse to fuck McCoy, because the captain did not take Christine lightly; he knew exactly how many people she'd damaged or killed for trying to take advantage of the supposedly helpless doctor. She'd been unconscious and Kirk could have easily taken her out of the equation — killed her, put her in the brig, kept her sedated, tied her up, or simply locked the goddamned door — so he wanted something from her, and he trusted her to recognize it.

She leaned on the jamb and took in the sight of the two of them fucking.

Her breath caught. Rough breathing and slick wet sounds colored the air. McCoy knelt on his own bed, hands and knees splayed wide to brace himself against the thorough reaming Kirk was giving him from behind. His head hung down between his shoulders, his usually-impeccable dark hair swaying haphazard and damp over his face as Kirk swung McCoy's hips forward and backward into his thrusts.

She laid a hand on her bare midriff, trying to quiet the arousal blossoming in her belly and between her legs. The captain's muscular body never stopped moving; lean, smooth, surprisingly youthful, only a few visible shadows of scars for all the times she knew he'd been injured. His short golden hair was rumpled, his blue eyes alert, watching for her.

"Oh — hi — Nurse Chapel," he said, panting measuredly like a marathon runner, gauging her for lethal intent even as he drove harder into McCoy. "I was — wondering — when — you might join us."

McCoy's head jerked up and he saw her in the doorway, his face flushing scarlet and not just from embarrassment. But he managed to convey with several quick microexpressions and one pleading quirk of the eyebrow that he was fine, really, and could she leave them be, please?

She folded her arms across her chest and let her eyes trace the lines of the collar implanted beneath the skin of McCoy's neck before returning her cool gaze to his face. Hell, no.

"You want to tell us what this is about, Captain? Or would you rather wait until you've finished?"

A slow smile, an appreciative nod; satisfied she was willing to talk, that she wasn't stupid enough to attack him.

"I already — told Bones, though I'm not sure — he heard me," Kirk answered, rhythm never slowing inandout. Blue eyes slid half-closed, half-glazed: a Siamese cat in mid purr.

She scowled at him, marveling that he was still reasonably articulate. His smile mocked her lightly, and he leaned forward over McCoy's broad back, changed his angle until McCoy was moaning again. The doctor's chin dropped, hiding his face and his kiss-swollen lips.

"She's mad about the hypo," he said against the pink shell of McCoy's ear, then straightened up enough to look into Christine's face. "You're mad about the hypo. I'm sorry about that, but I wanted some alone-time with McCoy, first."

No, she thought, you wanted me to believe you're not interested in hurting him. Why?

"You've had it," she pointed out, and received a blade-bright grin. McCoy tried to sink down on his elbows, but the captain wrapped a hand around his throat and tugged him up and back by the jaw, so that his ass rested on Kirk's thighs, his head tilted onto the man's shoulder as Kirk settled back on his heels. Eyes unfocused, as if he could escape her view by blurring his own, McCoy quivered in Kirk's grip, skin moist with sweat, cock rigid and flushed.

But she wasn't going to look at his erection.

Christine kept her eyes on Kirk's, waiting. His fingers didn't press in, didn't throttle, didn't do anything but stroke over the fine lines of the subdural collar, but McCoy's breath quickened despite the angle that had calmed Kirk's thrusting hips to a deliberate roll. His other hand rested on McCoy's belly between ribcage and navel.

"As I told him," Kirk said, more than a little breathlessly, "I want a puppy of my own."

Her eyebrows twitched together and McCoy hissed. If the inhibiting collar had allowed him — and if the spasms of his arousal had left him any real motor control — she knew he would be slapping the captain's hand away, but she was captivated by Kirk's faintly-raised eyebrow, ever so slightly curled lips, the sharp possessive look in eyes still fogged by pleasure.

"That look on your face should be illegal, sir," she observed, mind snapping pieces together like a broken bone settling into place.

She'd served under enough captains to know how commonly the ship's doc became the "Ship's Dog," thanks to the collar. There were even ships where the nurses didn't understand the necessity of protecting the Fleet's forcibly-trustworthy doctors, where captain and crew made the nickname half-literal. Doctors who were only human when they were treating patients, the rest of their time bounded by food bowls and choke chains and dog-tailed dildos; whether for cruel entertainment, or out of reaction to the persistent rumor that doctors were the Fleet's spying bloodhounds, more loyal to the Empress than to their shipmates.

But if Kirk wanted to play such games, he'd be starting right now, not rocking his way through a straightforward fuck. And he didn't just want a puppy, he wanted a puppy of his own. So he wanted McCoy's loyalty, to him.

"Ah — you'd look this way too, if you were me, Christine," he laughed salaciously, canny eyes still watching her put the puzzle together. What was it Kirk was offering him — them — in return?

"I'm much safer letting you be you, Captain." It was cruel enough having to watch Kirk taking McCoy apart, inflicting irresistible pleasures on him. To imagine taking Kirk's place — riding that hungry erection, or penetrating her doctor with fingers or toys of her own — that was torture. And a heady distraction that she couldn't allow, in the middle of a negotiation where she didn't yet understand the parameters.

Not that dicking and dickering were strange bedfellows for Kirk, apparently.

"Suit yourself," he murmured, picking up the pace again, whisper-light fingertips tracing the trail of dark hair down the doctor's belly. McCoy jumped and writhed involuntarily against the snug hand on his throat and the impaling cock; his hands twitched upwards but he stopped them, trembling in midair, before the collar could do it for him.

"Stop that!" he pleaded.

Kirk grunted with effort.

"I can't — help it — if you're ticklish, Bones." The teasing fingers skated lower, spread in a vee around the base of his cock, clamped down on McCoy's pubic bone and pulled his sliding body back up along Kirk's thighs with an obscene squelch of lubrication.

Kirk nuzzled smiling lips near the fingertips that rested on the paler skin of McCoy's neck, against the the tendrils of neural fiber and duridium alloy that threaded beneath; that passed through his spinal cord, trachea, and carotid arteries, and prevented him from violating the Fleet's conditioning to "do no harm." That kept him obedient to the Empire, whether he wanted to be or not.

Understanding overwhelmed Christine; she leaned for support against the doorjamb, and her lips parted. She had to swallow before she could speak.

"You really think you could hold his leash?"

Kirk nodded approvingly. "I think — a puppy — who knows his master — doesn't need a leash."

McCoy was staring at her, eyes wide at Kirk's words, but she could tell his mind was struggling to comprehend the implications while his body bucked helplessly between the thrust of Kirk's hips and the firm hands that held his throat and worked his cock.

Christine, leaping ahead, let herself blurt the first protest that came to her mind.

"You can't break the collar without killing the doctor." She stepped into the room, closer to Kirk and McCoy, thighs sweeping against labia that had grown hot, swollen.

"I — don't — have to — break it." The captain's breathing was harsh and wild as he lifted McCoy with thighs that had to be aching with sustained effort, until the two of them were upright on their knees, no longer resting back on Kirk's heels.

Almost too quick to follow, Kirk seized better leverage with a half-nelson: shifted his own knees back and apart, slid the hand off McCoy's throat, wrapped it under his armpit and gripped the back of his neck. Without a pause Kirk's heavy hand bent him a little at the waist, so he could drive harder and deeper without letting McCoy collapse forward.

"I — just — have to — ah, fuck!"

It was almost funny, Christine thought, clenching her fists at her sides, to be frustrated with the man for finally becoming incoherent while he pounded his way towards orgasm. But she needed to know; what he was talking about was too big, too important. Unleashing the doctor could change everything about her life, and McCoy's. Freedom —

She looked into McCoy's eyes, at the raw, defenseless arousal that swelled into gape-mouthed gasps and grunts. She saw him briefly through double vision: the handsome, confident, possibly cruel man he could have been, walking free under planetside skies, and the cautious, frustrated one he had become, chained to one small deck in a tiny ship amidst the hated darkness and silence of space.

But he could never have real freedom, she thought, swallowing hard. McCoy's exposed body jarred under Kirk's vigorous thrusts, hands dangling loose and undirected.

Even if Kirk could miraculously unbind him, McCoy couldn't just walk away from the Enterprise — the Fleet would hunt him down and kill him. They might kill everyone who'd been near him just to ensure no one ever heard what Kirk had done.

When Kirk's thumb and forefinger constricted around the base of his cock, smaller fingers cupping his scrotum up too, McCoy's noises grew louder, and then he found breathless words.

"Jim...Jim, what — oh... that's cheating..." McCoy actually sounded cranky, involuntarily straining to straighten his bent neck and spine, involuntarily driving Kirk deeper inside of him, and groaning at the result.

He was pinned, helpless on ten different levels, but still not weak for all of that, and the captain was delighted by the accusation, laughing and tightening the grip that would delay McCoy's orgasm until Kirk got all that he wanted.

Kirk intended to keep him. McCoy would have to stay with the ship — hell, he'd have to stay in Medical, have to flinch away from the crew, have to keep up the pretense that he was still constrained. Not free at all.

Kirk threw his head back suddenly, slamming in deep and stiffening all over, lifting and holding McCoy's whole body with rigid bone, muscle and cock.

Not free. But without the threat of punishment through the collar, McCoy would be free to act in his own defense, if the situation were desperate enough that dropping the act was worthwhile. He wouldn't be completely dependent on Christine for his safety anymore, which set a complex mix of emotions roiling in her gut; those would require sorting later.

Kirk swayed back for a fraction of a second, breath rattling in his throat, then slammed up into McCoy and held there again, and then a third time. McCoy cried out in agony or ecstasy or both.

McCoy would be free to take risks to save his patients, to operate in the dangerous-but-worthwhile gray area of medicine that the Empire's conditioning did not allow.

Christine heard her own breathing, raw and uneven; body winding tighter, mind trying to race ahead of Kirk's, to guess how this mass of physical, mental, emotional tension was going to go critical.

Kirk's gaze blazed like blue stars at the ceiling as he silently rode out his ejaculation. Kirk's plan would let McCoy be the doctor he had been, before he'd made whatever fatal mistake had drawn him to the Fleet's attention.

McCoy whimpered, muscles straining, hips forcing his desperate cock against Kirk's restraining hand.

Starfleet thought it was better for a patient to die from a serious wound than from risky treatment, since the alternative was to allow doctors enough wiggle room in their personal judgment to once again become deadly pieces in the grand bet-and-bluff game of the fleet hierarchy.

Kirk slumped.

Her heart skipped a beat.

He let his forehead fall against McCoy's shoulder.

Kirk was after a piece whose moves no one could anticipate. Slipping McCoy's lead, having a doctor who could act as he pleased, would allow Kirk one hell of an advantage. He would be able to make plans other players couldn't see coming, because they wouldn't think such a thing was possible.

"God damn it, Kirk," McCoy growled, voice rough with frustrated arousal and anger, fingers trying to curl into useless fists. Kirk slowly lifted his face, hooked his chin over McCoy's shoulder. His arm slithered free of the hold on McCoy's neck and wrapped firmly around his chest instead, supporting him as their knees bent and Kirk sank back onto his haunches.

Kirk's expression looked even more illegal now, powerful and sated, holding McCoy's body primed and spread before her like a gift. His eyes glittered with challenge, waiting for her to make a move.

Christine strode to the bed, pulse beating rapid and strong in her throat and between her thighs. She laid her hands on McCoy's passion-fevered cheeks, watched until the desperation in his eyes thinned enough for him to hear her.

"If he can give you freedom from this collar, Leonard, would you kill for him?"

Kirk's wolfish grin was a new, vertiginous type of praise. McCoy jerked and stiffened in his arms, shocked and overwhelmed.

"No! I don't kill. I'm a doctor, not — not — an assassin."

She shook her head. "You've had to let a dozen people die on your watch because that collar won't allow you to be a doctor."

Anguished hazel eyes, clouded with regrets and confusion, were pinned on her pale blue ones; he was still breathing heavily, and his tongue flicked out over his upper lip. Kirk continued to watch, possessive and provocative, still, except for the cupping fingers that lightly caressed McCoy's scrotum.

"If he can do this — and he has to prove he can — then you can save people, Leonard. You can make your own choices. You can decide whether and how to treat.

"We'll have to keep it subtle. We'll have to act like you're still restricted. But when it matters we'll be able to save a life. Or let someone die." Her eyes flicked momentarily up to Kirk's. "Or help them along."

"No..." McCoy struggled to sound firm. "I said no, and I meant —"

"Leonard. Listen to me. He's going to have to be be subtle too. He's not going to want anyone to know, so he's not going to call on you often." Now she kept her eyes on McCoy's, mouth dry, realizing the captain might think she was dictating terms. But she wasn't saying anything untrue or illogical. "He's going to have to save us for the ones who really deserve to die, the ones his usual resources can't touch. And no one is ever going to know — or even suspect — that it could be you."

She let go of his face and knelt on the foot of the bed, closer to him, not quite near enough to touch. Kirk seemed mesmerized by the excitement that thrummed in her voice, her body.

"And listen — listen. You'll be able to defend yourself, when it counts, when you're alone. You won't have to shrink back and pray help comes. And I won't need to be your keeper. I'll still be at your side, to sell the illusion, but you won't need my protection."

Something was kindling in McCoy's eyes. She eased one knee forward between their legs, stretched the other up the outside of his bent thigh and calf, the warm boot leather caressing his skin. Her skirt spread and wrinkled upwards as she straddled his thigh, letting him feel how wet she was.

"We won't need to be hands-off anymore, Leonard."

He lifted one hand, stopped it in mid-air, looking lost and overwhelmed, panting -- and then he brought both hands up to the fabric tied between her breasts. He dug fingers into the knot, and yanked the sides of the tiny shirt apart, baring her skin to the air and his molten gaze.

Kirk's eyes devoured her half-naked body, too, and he shifted his confining grip on McCoy's thickening erection.

Christine shrugged back, pulling the ties out of McCoy's hands and slipping the shirt off her shoulders in one smooth motion. When he hesitated, she took his wrist and pulled his palm up against the soft undercurve of her breast. His mouth fell open with a gasp as he kneaded thumb and fingers into ready flesh, squeezing just hard enough to awaken all the nerve endings before he captured her nipple. His eyes were riveted to the curves of her chest, to the sight of the nipple contracting in his tight grip.

She didn't try to stop the soft "oh!" that escaped her; she leaned into the touch, sliding a little higher on his thigh.

Kirk brushed his lips against McCoy's neck, hitched his hips up against his backside — he couldn't possibly be getting hard again already, could he? But then his lips nuzzled under and in front of McCoy's ear, and he whispered, "You haven't answered the lady's question, Bones..."

McCoy squeezed his eyes closed, shuddering all over in frustrated desire.

"God damn it Jim — you can't use wiles like this in order to get me to agree —"

Kirk snickered, low and cruel. His arm released McCoy's chest, maneuvered Christine closer.

"Your decision is your decision," he said, "and frankly I'd be disappointed if you gave in to me just to get off. But you have to admit, the rewards laid before you are pretty tempting."

She checked her irritation — being used as a bartering chip was nothing compared to how much she wanted their freedom, his freedom. She swung her leg over to straddle McCoy's hips, let Kirk's hand on her waist guide and steady her until her aching clit rode up against the knuckles of his hand on McCoy's cock. She stretched her arms across both sets of muscular shoulders, twining fingers behind Kirk's neck, leaning her breasts against McCoy's chest and undulating her hips.

He groaned.

"I'm asking you. Say yes, Bones. Please..." Kirk said in his ear, pressing his chest forward so that McCoy's torso was sandwiched tightly between his heat and hers. His free hand slipped into Christine's crotch, pushed her panties aside, nudged their bodies until just the head of McCoy's cock was clasped in the folds of her labia. "Pretty please."

"Goddamned son of a bitch...." he whimpered, eyes clear and determined. "Yes, yes, yes, I'll be your puppy, I'll be your hound, I'll play goddamned fetch for you...."

Christine caught the rest of his words with her mouth, and slid home onto his cock as Kirk pulled his hand out from between them. McCoy and Kirk groaned with almost the same note as she ground down hard. The captain wrapped both arms around her waist and helped to keep three pelvises in motion, McCoy riding taut and compressed between his two lustful co-conspirators. She continued to suck on his tongue and lips, savoring the complex bitter-bourbon taste of potential freedom, while his head lolled on Kirk's shoulder, shifting with every motion of Kirk's body.

She drove herself with abandon, clit riding tight against McCoy's hard pubic bone, molding her wet and yielding depths around his cock, hoping to reach her own release before his overtaxed arousal gave way. Kirk helped, hands roaming all over her ass, spine, ribcage, breasts, until he squeezed one hand beneath the waistband of her skirt and settled it over her tailbone, long middle finger snugged between her cheeks to threaten and tickle. He pulled her forward and back over McCoy's body, and she shifted her attention to nip at the pulse throbbing in McCoy's throat.

This time the keening whimper was all hers, and he jerked between them, every response out of his control. Christine held a thin fold of his skin in her teeth and rode his violent spasms, squeezing her leather-wrapped calves against their thighs until her boot heels dug into McCoy's knees. But the passionate pain she could inflict, the power she had over him at this moment — that she could have had at any time. It was knowing he'd soon be able to give it back, that they'd be able to wrestle for dominance, that together they would be Kirk's hidden blade and have that secret power over the rest of the crew, over the rest of the fleet — that was what drove her own flashfire orgasm, heat flushing through every limb and contracting with electric force every wet pink erogenous point in her body. Her wild cries mingled with his, and her shudders set off his, which set off hers again, until their unsupported bodies were too much for Kirk to hold up any longer.

Laughing at them both, he shifted and let them fall to the side so they flopped apart, separating too suddenly with a wet noise. She couldn't help a sigh of loss, and it took a moment before she had enough coordination to prop herself up on one elbow to look at him over McCoy's half-conscious body.

"Don't laugh too hard," she said, giving Kirk a feral grin of her own. "I still owe you for the damn hypo. And if you can't deliver...."

"I can deliver. And so can you," he rumbled appreciatively, stretching stiff legs. "And it's going to fun finding out whether our puppy grows into a wolf...."

McCoy made a sleepy noise of protest; Kirk squeezed his arm and she set her hand on McCoy's flat stomach. She rested her head on McCoy's shoulder where she could watch Kirk's face, and pondered the future whose shape she thought she knew.