anonymous said: As a full demon Sherlock goes into ruts, where his sexual desire for his mate supersedes everything else. Molly doesn't mind it a bit; even though she has to take two weeks off every time Demon!Sherlock's ruts are upon him.

NSFW, M rated, smexy times, warnings for anal, also the judicious use of a demon's tail as a sex toy, etc. Same warnings/commentary from The Devil You Say, basically. Smut, smut and more smut.

It would be so much easier if his ruts came on at predictable intervals; twice yearly, or one a quarter, something like that. But no, Sherlock just had to be the maverick even among his own famously chaotic kind; his rut cycles came two or three times a year, sometimes at six week intervals followed by months of normality – at least, as normal as a demon's life could be living amongst humans – sometimes spaced evenly every four or six months.

This year it seemed to be a seasonal whimsy; he'd had a half-length rut in the winter, another one in the late spring, and here it was summer, in the midst of heat wave the likes of which London hadn't seen in decades (some blamed a weather wizard, others global warming, while still others maintained that global warming WAS due to a weather wizard) – and Sherlock's behavior was becoming erratic, even for him.

That, in fact, was the only way Molly knew her beloved, irascible, socially inept and incredibly brilliant mate was heading into rut; his painstakingly learnt manners went out the window, what little patience he could manage vanished, and his temper…well, that went from 'short' to 'nonexistent'.

When John texted to let her know that Sherlock had a) insulted every single member of Lestrade's forensics team at the site of a supernatural crime, and b) had systematically trashed the kitchen of 221B when they were ordered off the crime scene, Molly sighed and put in a request for emergency leave straightaway, not even finishing the autopsy she'd barely begun. She left the body on the table, only covering it with a clean sheet and leaving a hastily scribbled note for Dr. Singh, explaining where she'd left off. Then she did a quick scrub-up and dashed down to the locker room to retrieve her handbag. She hesitated a moment, then decided on taking her blood-stained labcoat with her rather than chucking it in the laundry hamper. Balling it up, she tucked it into a plastic bin liner, tied it off neatly, then used her mobile app to call for a cab.

As soon as she arrived at Baker Street she popped into Mrs. Hudson's flat, advising the older woman that now might be a particularly good time for a visit with her sister in Leeds. Mrs. Hudson sighed and switched off the telly. "Again? That's the third time this year, Molly; not that I'm complaining, mind you, it's so nice not to have to deal with his tantrums like I did before you came along, but honestly! Why can't he be like every other demon and just go into rut twice a year, every six months, and not be all scattershot like this?" Then she tsked and headed into her bedroom to pack.

After taking care of Mrs. Hudson, Molly hurried up the stairs to the flat she and Sherlock had shared for two years now. Being a demon's girlfriend had taken a lot of getting used to, but once he'd coaxed her into cohabiting with him, things had actually gotten a bit easier. For one thing, she could officially register their status, and thus had no problem with time off for 'Special Circumstances' per the Demon Equality Act of 1988. For another, she was no longer living in a cramped bedsit; Toby, her spoiled half-Persian, half-something unidentified but vaguely feline 'cat' could roam about the entire building, including Mrs. Hudson's flat and the empty basement flat, shifting his shape from mouse-sized to lion-sized at whim without any other tenants complaining.

And, of course, there was the sex. The sex with Sherlock was always amazing, but when he was in a full demon rut…when his eyes glowed with an inner heat…when his skin morphed into silky-soft iridescent scales that made him shimmer under the moonlight…when his horns erupted, surrounded by the dark curls on his head that turned ebony black with glints of midnight blue…the way his prehensile tail felt twined about her body…the soft rustle of his wings as he moved above her…

Molly's rather heated reverie was interrupted by the sound of her mate bellowing at something in their bedroom. She closed the door behind her, knowing that Toby would have made himself scarce as soon as he scented the change in Sherlock, not to return until the rut had run its course. As a non-sentient demonling he wasn't exactly what Sherlock's demon rage would see as a challenger for his mate, but he'd learned not to take any chances; Sherlock's claws had nipped off the end of his tail once, and although it had grown back within a week, Toby never forgot. He'd gotten over his sulk about the time the tail regenerated, but was ever vigilant to Sherlock's moods and scent after that. If Molly hadn't been working extra long shifts this week, she probably would have picked up on the signs sooner.

Ah well, live and learn. She shucked her coat, laid her handbag and keys on the kitchen table – which had been returned to its upright position, although it was easy to see where Sherlock had tossed it and its contents about as John had reported – then began removing her clothing, listening carefully to any sounds from the bedroom as she did so.

Apparently Sherlock had either fallen asleep – unlikely in his current state of agitation – or else he'd retreated to his mind palace in order to attempt to calm himself. Either way it gave Molly the time she needed to prepare herself, which consisted solely of getting naked, tying back her hair in a braid, and then donning the soiled labcoat.

Taking a deep breath, she marched down the short hallway toward their bedroom, pausing only to backtrack and duck into the bathroom to grab a particular jar of ointment that was a vital necessity for any human female mated to a full demon male. Then she pushed open the semi-closed bedroom door and found Sherlock sprawled naked on their bed, his body somewhere between human and demon in the form she loved the best.

As predicted, he was deep in his mind palace, his eyes shut tight, fingers poised beneath his chin, one leg extended and the other pulled up, giving her an excellent view of his engorged cock. Oh yes, his rut was definitely on him; even her blunt human senses could smell the enticing fragrance his body was emitting, could feel the subtle electric current his skin was giving off as every hair on her body raised itself. "Sherlock," she started to say, but yelped and lurched back against the door in surprise as he suddenly opened his eyes and sprang from the bed.

As he screeched to a halt in front of her, his blurry form coming back into focus, Molly smiled and reached for him. He'd transformed into full demon mode during that half-second trip from bed to doorway: iridescent scaly red flesh, glowing golden eyes, sinuous barbed tail, glossy black wings, shiny metallic grey horns, inky black curls, elongated fangs and curved claws on hands and feet. Wordlessly she held up the jar of ointment, closing her eyes and inhaling deeply of his scent as he began to work the odorless material over every inch of her flesh, from head to toe.

She hissed in pleasure as he paused in his ministrations to lick a hot stripe up her pussy; he'd fallen to his knees in order to knead the flesh of her legs with the magically-infused ointment that would allow her to endure the bonfire heat that would come over his body as soon as the rut entered its second stage (which, judging by the heat of his forked tongue as it worked her folds, wouldn't be long now).

Molly leaned back against the doorframe, her hands automatically tugging at Sherlock's pearlescent horns. They'd reached their full, magnificent height and thickness, rising six inches above the tops of his hair and just the perfect size for her to curl her hands around. If it wasn't for the way they tapered to delicate points at the tip, it would almost be like holding two warm, hard cocks in her hands. There were some demons with multiple sex organs, and she couldn't say she hadn't entertained a fantasy or two when she found out that Mycroft Holmes was one of them, but Sherlock was more than enough demon for one woman to handle.

Besides, she had the feeling Mycroft's half-demon mate, Anthea, would likely rip Molly's head off if she caught so much as a whiff of those fantasies.

The labcoat had been removed during Sherlock's careful application of the ointment, but not before he'd sniffed appreciatively at the blood she'd gotten on it during the interrupted autopsy. Demons were like dogs in some ways (although she would never say that aloud!); they reveled in scents that humans found repellent or downright disgusting. And since there was a bit of effluvia on the cuffs as well, she knew he was thoroughly enjoying her little mating 'gift'. Not that he needed encouraging, but custom was custom and Molly prided herself on always being a thoughtful lover.

As did Sherlock; she gasped and bucked against his mouth as his tongue went deep inside her cunt, thickening and hardening until it was basically a human-sized cock. Molly's moans and gasps deepened; her grasp on his horns tightened and she spasmed and cried out his name as she came, further turned on by the knowledge that the sensation of her cunt tightening around his tongue was literally being felt on his actual cock at the same time – not to mention that she could feel his pleasure shooting through her limbic and nervous systems at the same time. Demonic biofeedback was still poorly understood by human science (even after thousands of years of study), but GOD was it amazing to experience!

Molly was still recovering from her orgasm as Sherlock eased his tongue from her body. It softened and returned to its natural state as he assiduously applied the ointment to her lower legs and feet, then spun her around to slather the back of her body with it, starting at her neck and working his way downward once again. When she felt his tongue probing at her backside she moaned and braced herself against the doorframe, widening her wobbly legs but making no complaints. Foreplay was literally of vital necessity during a demonic rut; if Sherlock didn't make her come at least three times before actually sinking his cock inside her body, he wouldn't be able to come himself. There was no biological explanation for this phenomenon, but it was a fact nevertheless.

A fact that Molly absolutely adored. Just as she adored the way his fingers – claws fully retracted at the moment – spread her arse cheeks wide. Just as she adored the sensation of his tongue as it slicked itself down her crack, the tip slipping into her puckered hole then sliding back out again as she moaned and tried to keep herself from bucking back against him. Knowing how he liked to tease her when he still had some semblance of control over himself.

Hearing his dark chuckle, she turned her head and mock-glared at him. "Stop messing about, Sherlock!" she snapped, wiggling her arse just a bit as he pressed a series of hot kisses to either side of where she wanted his mouth. "Please, you know what I want!"

"And what might that be, Molly?" She shivered and bit down on her lower lip, almost hard enough to draw blood; his human voice was silky and deep, a baritone that sent shivers down her spine, but his demon voice was deeper still; a rumbling bass she felt as much as heard as it went straight to her already dripping core.

"Use your tongue," she begged, not caring how needy she sounded, knowing that it only served to further arouse him. Demons might not be actual creatures of a biblical devil as mankind had believed for so long (but rather were interdimensional travelers who had become trapped on Earth during the late Jurassic period), but they still thrived on the submission of their lovers at some visceral, purely instinctive level. With a demon there was no safeword, nor any need of one; a temporary emotional bond formed during a rut that allowed the demon to know exactly how willing his – or her – lover was at any given moment during their joining. No demon was ever so mindless as to do something to their partner that wasn't fully desired. And Molly had learned to fully desire quite a bit over the past four years of their relationship.

Such as the feel of his tongue sliding inside her arse, as it was doing now, his amused chuckles vibrating within her body and making her whimper with pleasure. She couldn't restrain herself a second longer; her hips snapped and she bucked against his hot, wet mouth, feeling his tongue slowly hardening again as it worked its way deep inside her.

Molly moaned again, hoping distractedly that Mrs. Hudson had already vacated the premises, as she didn't think she could keep her voice down for much longer. Then Sherlock reached around to the front of her body, insinuating two long fingers deep inside her dripping core, and she screamed his name as he made her come for the second time in less than ten minutes, his thumb rubbing against the swollen nub of her clit and his tongue working its not-so-evil magic deep inside her rectum.

She collapsed as he pulled himself away from her with an obscene slurping sound; he caught her before she hit the hardwood floor, holding her close as he carried her to their bed. One more orgasm and he could enter her the way she most wanted and needed; the near-pain of his aching cock was being transmitted to her body, causing her to tremble and moan as she instinctively reached out to grasp that burning hot appendage.

As usual Sherlock had made sure to apply the ointment – which magically replenished itself in the ever-full container they'd paid a pretty penny for – to every part of her body that would come in contact with his: between her fingers, over her lips, even inside her mouth and over her ears and eyelids. It gave their kisses a certain slickness, but the honey flavor was like ambrosia to both of them. As he covered her body with his, Molly pulled his head down to taste of that ambrosia, her tongue thrusting deep into his mouth as he opened beneath her insistent kisses. She loved the way his kisses tasted and felt even when not during a rut: in human form he was sweet and gentle in a way that had both pleased and surprised her; in his demi-human form he was more demanding, rougher, but still nowhere near as wild and desperate as he was in this form, the form he only took with her when in rut.

His wings rustled as he adjusted his body against hers, sliding his cock along her slit in order to get some small measure of relief while he busied himself with her breasts, kneading them, teasing the already-hardened nipples to painfully taut nubs, and eventually sucking and nipping at them while her hands once again buried themselves in his hair. His horns had a measure of sensitivity to them around the bases, and she grasped them desperately as soon as she felt him moving lower on her body. This time his tongue remained soft, caressing her folds, only the tip occasionally dipping deeper within her pussy. He held her open with his thumbs, teasing her with his tongue until she hoarsely begged for him to suck her clit into his mouth. He did so willingly, enthusiastically, even; she sighed and squeezed her eyes tightly shut as he worked her mercilessly, dragging out the inevitable for as long as they both could stand.

Her orgasm was deeper, more intense than the first two had been, another side-effect of the demonic biofeedback they were both experiencing; from now until his rut concluded in approximately fourteen days, each orgasm she experienced would incrementally increase in intensity until finally she would be unable to remain conscious from the flood of pleasure washing over her body when she came. The first time she'd passed out during sex had unnerved her; now, she was used to it, or at least had become accustomed enough to it that she simply shrugged it off once she regained consciousness. Apple juice always helped, and she knew Sherlock would have a glass ready for her once she reached that stage.

Sherlock's body rising above hers, his tail twining around her legs, brought her out of her post-orgasmic daze and thoroughly back into the moment. He lowered his body over hers, his wings folding tightly against his back as he slicked the head of his thick, hot cock over her cunt. Molly spread her legs wider and reached down to tug his tail up; with a sultry look, she sucked the barbed end into her mouth, careful not to puncture herself with the sharp tip, knowing how incredibly sexy he found it when she did so even though the tail wasn't normally considered a demonic erogenous zone. The fact that he was actually much more sensitive there than most other demons had been an accidental discovery on Molly's part, but a happy accident for both of them.

She continued to suck at the tip of his tail as he groaned and positioned himself, finally driving deep within her body. Her hand tightened convulsively on the whip-like appendage and she tilted her hips to allow him better access before finally giving up and popping his tail out of her mouth so she could give full throat to her cries of ecstasy. Her hands slid down his back to grasp his wings, fingers digging into the leathery protrusions furled so tightly against his scaly flesh. Eyes clenched tightly shut, she felt herself on the verge of her next orgasm as he pistoned his hips, pounding into her desperately as the rut fully overcame him. If she looked at his eyes she would see how the pupils and irises had utterly vanished, giving way to a speckled silver that never failed to enthrall her. However, she was too lost in her own pleasure to be able to pry her eyelids opened, and put off that particular pleasure for a far more visceral one. They often came at the same time, their emotional and physical bond serving to synchronize their bodies' reactions, and this time was no different; Molly screamed, Sherlock bellowed, and she felt the hot gush of his cum deep inside her womb.

His cum. Inside her.

Shit.

Molly's eyes snapped open and she stared at Sherlock, heart pounding, breathing ragged, but not entirely from physical exertion. "What is it?" he demanded as soon as he was able to speak, her sudden panic flooding through their bond. "What's wrong?"

"I, uh, my birth control implant," Molly stammered out, tears forming in the corners of her eyes. He reached up and tenderly wiped them away. "When I checked the strings this morning…shit, Sherlock!" she wailed as guilt and panic threatened to overwhelm her. "They weren't, they weren't there! I think my implant came out, and I was going to call my GYN but it was so busy at work that I completely forgot, and then John texted me and all I could think about was getting h-home to you and…"

Sherlock silenced her with a kiss; not the forceful kisses she'd grown used to in his fully demon form, but a tender, loving kiss like those he shared with her when he was simply Sherlock Holmes, consulting detective. The man she loved. "It's all right, Molly," he said soothingly, pressing an equally tender kiss to her forehead. "Please don't be upset. I'm not."

"Y-you're not," she agreed wonderingly, knowing he couldn't lie about his feelings. Not to her, and especially not right now. "Why aren't you upset?"

He chuckled and shifted their bodies so that he was curled protectively around her. "Why do you think my ruts have been so erratic, love? It was my body's way of telling me it was time for me to procreate. Only I didn't think you wanted children, or at least," he added, suddenly sounding very human and very vulnerable, "not half-human demon spawn."

"Oh." Molly went silent as she mulled over what he'd just revealed, touched that he was willing to be so open and honest with her when just five years earlier he'd been so cautious of his heart that he'd surrounded it with a fortress of ice and disdain. "So…biologically speaking, you're ready to be a dad," she said tentatively, only to receive a rueful chuckle in response.

"Um, not just biologically speaking," he corrected her softly as he nuzzled against her neck. He'd yet to mark her, to bite her, to pierce her flesh with his fangs; that would come later, most likely during their next mating a few hours from now. "I'm actually…that is to say…if you think it would be all right…"

She laughed softly and turned in his embrace, pressing a soft kiss to his lips, silencing him the way he'd just silenced her. "Sherlock Holmes, if you're asking me if I'd be willing to bear your get, then you should already know the answer." She looked up at him expectantly, smiling as she saw his eyes widen with understanding. The love flowing through their bond was going both ways, rebounding and growing as he realized exactly how happy the thought of being a mother – the mother of his children in particular – made her.

"Molly Hooper, you are a wonder," Sherlock pronounced before drawing her close and giving her a kiss that was decidedly hungrier than the last few they'd shared. He growled and raked his claws lightly along her back, not hard enough to draw blood, but hard enough to make her arch and squirm and sigh with pleasure. "At the end of this rut cycle, if you aren't pregnant with my get then we will certainly work to remedy that situation!"

For her part, Molly had absolutely no objections.