Originally received 2014-09-15.

Cross-posted from AO3 same-day.

It took every bit of Sherlock's control to not break down his omega's door. The alpha could smell John just on the other side, the heat he'd been locked out of for the last several days finally on its last leg. With a sharp fluctuation and a high cry, his unmated mate came the last orgasm of his estrus.

The energy on the other side of his barrier dissipated and Sherlock relaxed for the first time since John had disappeared behind the door. This was the easy part, compared to the rest of it. As soon as his omega woke up, he would emerge, would allow Sherlock to clean him and settle him in for a long, hot bath as the alpha blazed like a wildfire through the spare bedroom they only used now for storage and John's heats. Most alphas liked to luxuriate in the scent of their omega's heats, but Sherlock couldn't stand to be around the evidence that, once again, he hadn't been allowed to service the man he loved more than anything else.

He knew why he hadn't been allowed. The week before John's first heat in the flat, months before Sherlock had even worked up the courage to ask the omega to be his, Mycroft had appeared and slid a file across the table. The alpha had gotten as far as shot and stress-induced heat and alpha doctor before slamming the folder shut and banishing his brother from the flat. After John had agreed, the omega himself had confirmed the file's report with avoided eye contact and twisting fingers and vague statements that still made Sherlock's stomach roil with impotent rage. He knew Mycroft had taken care of it, but it didn't stop him from needing to resurrect the dead to satisfy his alpha instincts and urges.

The door against his back suddenly opening jarred Sherlock from his thoughts and he was on his feet in seconds, walking his trembling partner (he couldn't even call him a mate because the marking had to be done during the omega's heat) to the toilet. As soon as he had John situated in the bath, the alpha was back in his flatmate's old room, flinging open windows and bundling sheets.

He remembered the first time he'd cleaned up after his new lover's estrus; he'd burned the sheets. John had been furious. Now he just dumped them in the wash with more detergent than was necessary and let Mrs Hudson take over the rest as he tended to his omega's needs.

The next few days would be filled with tired cuddles where Sherlock had to take care to not touch John on his scarred shoulder, his belly, his pelvis, his cock, the front of his thighs, the back of his thighs, his arse. It had taken nearly three heats to figure out he should just lay down and let his omega curl into or onto him however he wanted while Sherlock shoved his hands under his legs to prevent himself from curling around his love. It wouldn't be over till he woke up to John riding him with a wicked grin and heated eyes; John's conscious mind could handle any kind of sex Sherlock was interested in which, yes, the alpha loved, but it was the fact that his love's unconscious mind couldn't trust him enough to let him in during his heats that was slowly driving a stake through his heart.

"Can we bond?"

Sherlock didn't lift his gaze from his microscope. The mere reminder of his failure to comfort and support his omega when John needed him most always made it hard to look the man he loved in the eyes. "It is possible I have deleted the relevant information, but I was under the impression that that was only possible with intercourse during your estrus."

There was a pause and then, "I know." John's voice was quiet in a way it didn't normally get, and perhaps it was that that finally made Sherlock look up.

"Then-" he started to snap and then immediately stopped. His partner was standing in the doorway, gaze averted, hands jammed in his pockets, face red. But most importantly, he was radiating the scent of fear. Sherlock didn't know whether John's comfort and sense of security would improve if he moved closer or further away. So he stayed where he was. "Then why would you-" The alpha started again, a bit softer than before, before cutting himself off a second time as John's statement registered. "Oh."

"I mean," the omega started, face reddening and eyes landing anywhere but Sherlock's face as he stepped backwards. "You don't have to if you don't-"

Sherlock dropped to his knees so hard and so fast that the slide balanced precariously in his microscope's embrace rattled then fell and shattered on the worktop.

"Please," he croaked, voice sticking in his throat as his heart swelled at the idea. "Please let me make you mine. I'll do whatever you want, whatever you need. Anything. Just please, John. Let me mark you," Sherlock begged, fingers curling in the fabric of his trousers. He must look and sound a sight: a well-dressed alpha on his knees, begging his omega for something every other alpha took for granted that they could leave as many times and as often times as the fancy struck them. Sherlock had never even had the pleasure of pressing his nose to his omega's scent gland when he was in heat.

John blinked at him for minutes that went on for far too long before turning his head away, the blush on his face renewing. "I- I'm going to try," he said, voice firm. "I know I can't be be making this easy on you, and I'm really sorry. I can't guarantee I'll be able to this time either but-"

Sherlock didn't want to hear the rest. He knew it all already. The alpha crawled forward on his hands and knees, stopping in front of John's legs and wrapping his arms around them. "Thank you," he whispered, arms tightening as he nuzzled the crease of a his omega's pelvis. "Thank you, thank you, thank you."

The bullet blew a hole in his shoulder, destroyed the nerves in his dominant arm, bereaved him of his steady surgeon's hand. The infection ignited a fever that set his very blood on fire, made his skin itch like it was covered in fire ants, boiled his brain his skull until only hallucinations were left alive. Then, overriding a decade of military-grade suppressants, came a stress-heat.

The doctor watching over him had been an alpha, and when John had been at his most vulnerable, his most unable to consent, the doctor had made a decision for him that he would never have made, for himself or for his own patients. It ruined his ability to enjoy his estrus, left him alone and destroyed in a city he loved but didn't know how to exist in anymore. The knowledge that the alpha had been dishonourably discharged did nothing to console the omega when he was staring down the barrel of his service weapon, the sole occupant and visitor to the dingy, military-provided bedsit.

Sherlock had been a godsend. He was everything John needed in life and everything he wanted in a mate. He thought his love would be enough to overcome his past, that they would be able to bond and his past would no longer come back to haunt him four times a year. But then he woke and felt the slick between his legs for the first time since Sherlock had asked him out, and John remembered mouth hands cock tasting touching taking. He'd panicked, locking himself in his old room, determined to endure it alone and not pollute the man he loved with his soul-deep taint.

He knew it wasn't easy on his alpha. He could hear the man just on the other side of his door every estrus, scratching and whimpering. Begging, when he had his voice. It hurt, knowing he had someone right there who loved him and wanted to care for him, someone he loved and wanted to care for him, but he couldn't let them. He knew the inability to mark him and bond with him was slowly driving Sherlock round the bend as the seasons passed- his alpha was getting more possessive the longer they remained everything but bonded, going as far as to not take cases, so that the omega had less reason to leave the flat, less reason to go out into the world unmated.

So John thought long and hard, corralled his fear and came up with a plan, like any good captain, on how to overcome his trauma and do right by his mate. He waited until he was close to his heat and announced his intentions to his startled and warily hopeful alpha. Now that he was hard and leaking in bed, Sherlock snoring softly next to him and the scent of his alpha thick in the room, Captain Watson could only lay there, frozen in terror.

"Good morning." The sleepy murmur from the man at his side had the omega off the bed and trembling against the bureau in a panicked second. Sherlock shot upright and reached out for him before freezing, eyes dilating and twin spots of red appearing on his cheeks. "John," the alpha whispered, voice suddenly hoarse.

The omega didn't move, just waited for the leap, the attack, the pain, all while the thickening scent of alpha arousal made his cock pulse and his arse clench around empty air, the backs of his thighs unpleasantly sticky from the sheer amount of slick he was releasing. To his somewhat surprise, Sherlock withdrew, shaking fingers curling in the bedspread as the consulting detective's face cleared of emotion.

"I need to know now if you've changed your mind, John." Despite his lack of expression, John's lover's voice shook as if he could barely restrain himself and his fingers looked close to ripping holes in their sheets. "I can't- I don't think that I can restrain myself for long. If you need me to leave, I must know now or I may harm you in my enthusiasm."

It was that offer more than anything else that affirmed John's decision. He shook his head and started to move away from the dresser, every move slow as his eyes kept careful track of the alpha's position and movements. "I haven't changed my mind," he assured, his own voice just as hoarse. "But I need- Can I… tie you up?"

Sherlock's spine went stiff, his eyes wide, and John flinched, prepared to be rejected. "Yes, John," the alpha stressed, his face now the picture of earnest need. "Please. I will do anything you need." Sherlock licked his lips, tongue dancing over the pointed edges of his canines, the teeth that would, if everything went as they hoped, very shortly be embedded in John's scent gland. The omega paused, and then opened the middle drawer of their dresser, unable to take his eyes from his alpha as he dug around blindly.

The cuffs were easy to find amongst the rest of their sex toys, the two circles of leather linked and each trailing a length of rope knotted to each D-ring. The other end of the rope ended in a noose, a brilliant system Sherlock had rigged up to easily to tie himself to the bedposts months ago, a present for John when he came home from work that day. They had both been bound with ease and without care time and time again, but now the doctor's steady fingers shook as they caressed the familiar, worn leather.

"Toss them to me," Sherlock instructed, his voice quiet and undemanding. John blinked at him and then looked down at the cuffs. "I will put them on myself. You don't need to come near me until you're ready."

The ex-soldier had to look away as he tossed the leather and rope to the bed, but he could hear the slide of the softened material sliding over itself and two buckles put in place. When there was only silence again, he looked back to find Sherlock's arms spread to each bedpost, the man's back to the headboard and his legs straight out in front of him. The covers had been shoved to the floor and the alpha's cock was already hard and dripping precome where it jutted out, long and flushed, from between his thighs. There was nothing left of the stormy irises from where the doctor was standing, only blown pupils.

"My omega," the alpha growled, his voice so deep that it was almost unrecognisable. "Taste," he purred, his eyes traveling down and up John's shaking form, pausing longest on the unbound man's uncontrollable erection.

The ex-soldier was trapped in a strange shroud of deep terror and arousal. He'd never seen Sherlock in a heat-ignited rut before, never witnessed what his heat could do to his alpha. The man was twisting his wrists in his bonds, his back arched away from the headboard as he strained to get free.

"Mine," Sherlock rumbled. "Taste," he said again, licking his lips. "Come. Lick."

This was… different than before. Last time, the alpha had taken without words, hadn't needed to restrained, had just… taken. And John's biology hadn't let him say 'no'. He'd needed in a way that he couldn't temper, and he'd been helpless in his own rape. This time he wasn't helpless, though. He had offered, invited. He wanted. He wanted to give his alpha this assurance, he wanted to give Sherlock the bond they both craved, that they both needed. But the thought of a cock inside him, being knotted, froze him. He wanted to believe Sherlock wouldn't hurt him, he knew Sherlock wouldn't hurt him, but his prior experience tainted his trust. 'Trust problems' Ella had called them. She hadn't been wrong.

"Omega," the alpha growled, twisting and tugging harder now. The bed posts were creaking with the force of Sherlock's struggling. "Taste. Bond. Now."

Heat was turning his skin to fire, was making his arse clench around empty air, the tip of his cock dripping with precome. He was hot and wet and shaking and getting desperate. He could still do it, run up to his room and stuff himself full of silicone, leave Sherlock strapped to the bed where he couldn't get out, couldn't get to John, couldn't take what John was terrified to offer. But the second he took a trembling step, Sherlock stilled, dilated eyes watching, waiting.

The alpha's mouth was parted and his chest was heaving as if it was difficult to draw breath. His skin was flushed red, and the sheets between his thighs looked soaked with the precome trailing down his cock. John took another step and the alpha licked his lips. His terror had drawn all his attention to the sight in front of him, that it took him until now to scent the flood of pheromones in the air: arousal and possession. They made slick drip down his thighs, and Sherlock's eyes darted to the trail of liquid John could feel making a path across his burning skin, making it itch with the desire to be licked up. The alpha licked his lips again, and then darted his tongue out, eyes fluttering as if he was tasting the air.

The doctor moved a hand between his legs, swiped up that trail on two of his fingers, and brought his shaking hand out in front of himself. His alpha's eyes zeroed in on the digits with a hunger that made John's heart pound in his chest. He took another step forward, arm fully extended, and then another, bringing his trembling limb closer and closer to the most dangerous thing he'd ever encountered. Sherlock's body remained still, and his eyes remained fixed on the slick-dampened fingers, the tip of his tongue now permanently outside of his mouth, patiently waiting to taste.

John had to steel himself against jerking away when the front of his thighs pressed against the mattress, and the tips of his fingers landed on that extended bit of his alpha's tongue. They were sucked into a hot mouth with a speed that made him gasp and shake, the man's tongue sliding in between and around, flushed cheeks hollowing, as that mouth sucked and licked all the slick from his two fingers. Blunt teeth closed over the digits, firm but not overpowering, preventing him from pulling free. He could feel the substance being cleared away bit by bit, and the second the last trace of sticky was gone, the teeth released him and he yanked his hand free.

"More," the alpha rasped.

As much as it scared him to do it, it meant he could be a coward for a bit longer and keep that enormous cock away from where he was most terrified to put it. So he reached behind himself to press two fingers into his hole, where it was already loosened in preparation to take an alpha, before pulling them back out and offering them to Sherlock's hungry mouth again.

He did it over and over again, feeding the alpha his slick, waiting for him to calm down, but he only grew more aggravated with time, straining against his bonds harder and harder until his wrists were chafed by his efforts. The fact that John couldn't figure out why just scared him more. It wasn't until he realised he was pressing four fingers into himself that Sherlock rejected his hand with a turn of his head, and John's slick smeared across the sharp cheekbones.

"Enough. Breed. Now," the alpha demanded, planting his feet on the bed and rolling his hips.

The long alpha cock with the slightly swollen knot swivelled in the air, and despite his fear, the sight of that which could quell the need in him made John harder and wetter. The pheromones in the room skyrocketed in response to the increase in his arousal, and he found himself now to be the one licking his lips. There was a low, insistent growl from the man strapped to their headboard, and John's eyes snapped up to meet his lover's.

"Breed. Now," Sherlock stressed. John didn't bother mentioning him he was on birth control. The primal part of the alpha's brain that currently ruled the genius wouldn't understand the concept.

The omega's legs and arms were shaking as he climbed onto the bed, and he was thankful that the long legs lowered back down, giving him room to climb over them. It felt like his heart was pounding in his throat as he rose to his knees and straddled his lover's hips, the hot line of a thick erection grazing his arse. He froze again then, remembering, always remembering during his heat. Would that one experience rule his entire life?

His alpha rumbled soothingly, brushing his nose along John's cheek, a standard gesture of comfort that nonetheless made him tense anew. Still, Sherlock didn't stop, just kept rubbing their cheeks together, waiting for John to relax. But he couldn't relax. He wanted to, but he couldn't. He was already this far though, and he had no doubt that, should he try to withdraw now, his alpha would do everything and anything he could to get free of his restraints and mount him. John wanted to avoid that at all costs. He had for them to bond, and the look on Sherlock's face when he offered had almost broken his heart. If he could keep himself in control long enough to get through the first round of his heat, then he would be lost to his own biology and he wouldn't want to fight the man that he didn't want to fight.

John steeled himself then reached down and back to wrap his hand around the hard, hot tumescence, keeping it steady as he lowered himself onto Sherlock's cock. The second the head breached him, he had to stop. It had been so long since he'd had flesh inside him… No. He couldn't think about that while his mate was inside of him. He pressed his palms to the man's chest and dropped his head down, pressing his nose to the comforting scent of Sherlock, breathing in the familiarity of his alpha. With his nose pressed to Sherlock's scent gland and hands to skin, he lowered himself the rest of the way down and didn't dare stop until the man was fully inside him.

"Mmminnne," the alpha rumbled, lips brushing against John's scent gland. The omega startled at the touch and automatically tried to slam the side of his head into Sherlock's. Before he could make contact, teeth closed over the skin of his neck and he drooped against his alpha's chest, immediately pliant. "Yes. Mine. My omega," Sherlock purred darkly. John could only pant in helpless fear and need.

The legs under and behind him shifted as the alpha planted his feet against the bed again, his knees drawing up into a wall at John's back, a valley to keep the terrified and aroused omega trapped. Suddenly, the hips under him thrust up sharply, lifting him slightly before he fell back down onto the alpha's cock. His fingers curled, nails digging into that pale-but-flushed skin, as he was emptied and filled on repeat, the unending thrusts of the alpha's hips never losing power or rhythm, and the teeth against the sensitive skin of his neck remaining firm to keep him limp in Sherlock's lap. Despite being lashed to their bed, it was still the alpha with all the control.

The swelling knot inside him was growing bigger and bigger, was having a harder time pressing into him, and it got so large that it made him cry out in pain when the too-large bulb, on one thrust, stretched him wider than it ever had, but didn't pierce. When Sherlock's hips thrust up again, the teeth at his neck bit down, piercing his skin as they pushed down and his alpha thrust up quickly as the omega fell down. The knot popped past his rim, inflating as soon as it was inside and pulsing hot come into his insides and John sobbed as he came between them.

He was still panting as his orgasm faded, and with the loss of the shocks of pleasure also came the loss of the teeth in his scent gland, though a tongue quickly replaced them, laving over his new mating mark. The fear was a distant buzz, still present, but relegated to the back of his mind to give room to the happiness and satisfaction of finally being mated to the alpha he had chosen.

"My omega," Sherlock whispered between licks. "My mate. My John."

"Sherlock?" John's voice cracked when he spoke, and he couldn't find the energy to lift his face from his alpha's-his mate's- neck.

"I'm here. I'm sorry I lost control. Are you all right?" The alpha's voice remained soft, and he began to alternate between licking and nuzzling, running his nose along the line of the omega's jaw that he could reach.

"Yeah, I just- Yeah, I think so." The body under him tensed as the cock and knot in him pulsed more come into his insides, another wave of balm against the temporarily-banked fire. "Being able to scent that it's you helps."

"I thought no scent could be better than yours," Sherlock whispered against his skin. "I was half wrong: nothing will ever smell better than your scent soaking up mine."

John's heart thumbed in his chest and he licked his lips as he ground down instinctually on his mate's knot. "Yeah?"

"Yes. And the second you feel comfortable enough to let me out of these cuffs, I'm going to lay you down and cover every last inch of your skin in my scent," the alpha promised, voice low and intense.

A tongue licked slow and thick across his bondbite and John shivered, his hole spasming around Sherlock and bringing forth another flood of semen. After a pause, he reached trembling fingers out to the buckle on one of the cuffs, preparing to undo it, but then his mind was overtaken by images of Sherlock laying him on his back, holding him down, licking and scenting everywhere, mounting him, and he snatched his hand back as if the metal were burning, his fingers trembling.

"I'm sorry, I can't. Not yet." He buried his face in Sherlock's neck, wrapping his arms tightly around his mate.

"Shhh. It's all right. I promise," Sherlock murmured against his temple, nuzzling against his hair. "Take all the time you need."

The alpha's knot deflated, but John made no move to get up. Instead, he curled tighter around Sherlock and forced himself to calmly breathe the scent of his mate. The hard part of his heat was over, and he would never be able to convey his gratitude to his partner how much Sherlock's patience and understanding meant to him, but the continued whispers of comfort and unending scenting told him that the genius already knew.

FIN

I had an oddly hard time with this one.

Thank you for reading! Please let me know what you thought, good or bad, in the Comments, and if bad, please be constructive so that I may better my writing! :3 Also, if you liked the story enough to want to promote/rec it on tumblr, instead of creating a new post, please reblog either the original prompt fill (themadkatter13fanfiction tumblr, post/111598124628) or the typical story info post (themadkatter13fanfiction tumblr, post/111598166123)! Thank you so much! You are, of course, also more than welcome to follow me on tumblr as well! :3 Tschüß~