A/N: Warnings for dubcon sex (nothing graphic) and Jim Moriarty's sticky situation.

Molly held him close, pressing her body against his, breathing in the changes to his scent as her pheromones continued to flood the room, to intoxicate his senses. She'd begun releasing them once she'd closed the door, in anticipation of his rejection of her pleas, and soon, very soon, he would succumb - not to her 'charms', meager as she acknowledged them to be, but to the very fact of her biology.

Oh Mama, oh Papa, I'm sorry, I know I promised but Sherlock's life is at stake, I hope you understand.

Unknowingly, unthinkingly, unwillingly.

And now, in the coldest of cold blood.

But only after giving him one final chance.

He shook his head, his eyes refocusing on her as he came out of the daze into which he'd fallen as her initial pheromone burst dissipated somewhat. Oh, he was still under her sway whether he knew it or not, but for a few, vital moments he would have his clarity of thought. Would it be enough? Probably not, she acknowledged, but surely even the slimmest chance should be grasped, no matter how the family curse bubbling through her blood urged her to just get on with it.

"Please, Jim," she breathed, nuzzling his ear as his hands continued to roam over her body. "Whatever your plan is, stop it. I'm begging you."

Molly, I think I'm going to die.

No. She would never let that happen. Not to Sherlock.

"Mm, no can do, Molls," Moriarty murmured in response, his hands gliding down her back and settling on her waist, his thumbs absently caressing her midriff. "Sherlock has to die. This fairy tale doesn't get to have a happy ending." He smiled, that sharp, toothy shark's smile. "Well, except for me. I was tired of it all, you know, ready to pick up my gun and BOOM!" He mimed holding a pistol to his head and shooting, eyes and mouth comically wide. "But suddenly Little Miss Perfect called me out of the blue and I realized two things: she wasn't at all what I thought she was, and she meant more to Sherlock Holmes than I'd been led to believe."

He kissed her again, then pulled back so he could see her face, read her expression. "How does that make you feel, Milly-Mandy-Molly, hm? Knowing that you just gave me even more ammunition to use against your not-boyfriend? Oh yes, this is going to be absolutely delicious." He lowered his head so his lips brushed against her ears as he whispered, "The things I'm going to do to you, Molly love, will make you wish I'd just set a sniper on you, the way I did his other pets - that bitch of a landlady, the copper, John Watson...I can't wait to see how Sherlock reacts when you and I go to meet him on that rooftop later."

So. That was that, then. He wouldn't back down, wouldn't spare the others no matter what she offered, no matter how much she begged or bargained.

Fine. She'd tried.

Turning her head just the smallest bit, just enough for their mouths to meet, she kissed him again. Desperately, greedily, letting slip her last vestiges of control, allowing the monster that dwelled within the freedom to do what it - what she - so desperately wanted to do. What biology now demanded of her. Surrendering to instinct, as the women in her family had done for countless generations, she released a further burst of pheromones that clogged his every sense, narrowing his focus until she was the only thing in his universe, and he in hers. Deepening the kiss, pulling him closer, ever closer, so close they could hardly be told one from the other except no, they were still separate, still apart when she needed him closer closer closer…

Now

Jim Moriarty was a man who prided himself on his self-control. Even more, he prided himself on his ability to control everyone around him, to make them dance to his tune, to do what he wanted them to do.

If he'd been able to form a single, coherent thought, it might be along the lines of wondering when, exactly, had boring, ordinary little Molly Hooper gained the ability to turn him into her bitch.

But he was far too busy wildly enjoying himself as they writhed together on her luxurious king-sized bed with the down mattress topper and 500 thread-count sheets and silky duvet and oh, they were about to absolutely destroy that bedding what with all the mind-blowing sex they were about to have, were having,had already had? would have again and again and again and again and again and ag…

He came back to himself slowly, drowsy and sated and with a coppery taste in his mouth that he recognized immediately as blood. Had he bitten her? Yes, yes he had, right on the neck, like some movie vampire, the Dracula of the criminal world. Goodness, that must have hurt but he didn't remember hearing her scream, pity, that.

Well. She hadn't screamed in pain. She certainly hadn't kept her wails of pleasure to herself! "Lady on the streets, wildcat in the sheets," he murmured and started to lift himself from where he'd (apparently?) just collapsed on top of the woman who thought her meager charms (which, to be fair, weren't nearly as meager as they'd appeared at first blush) would be enough to tempt him into sparing Sherlock fucking Holmes' life.

He couldn't move. Not his head, not his hands, not his legs...what the fuck had the little bitch done to him? He hadn't had anything to drink or eat (except her, was that how she'd done it, paralyzed him, numbed him, had she laced her ladyparts with some drug he'd ingested, yeah, that had to be it, no other explanation, he'd have felt her jabbing him with a needle, no way was any piece of ass so good that he'd have missed something that obvious-)

"What the fuck did you do to me, you stupid cow?" He could still speak, that was a plus, although his lips felt as numb as the rest of his body. And he could move his eyes; he could see that he was still lying where he'd collapsed atop her, his cheek to her shoulder and the wound he'd made in her throat still sluggishly bleeding; he found himself oddly tempted to dart out his tongue and catch those glistening red drops between his lips, and resisted only because he couldn't fucking move… "What the fuck did you do to me?" he screamed again, struggling to move any other part of him and failing.

Jim Moriarty never failed. At anything. And whatever drug she'd dosed him with would eventually wear off (unless it was poison, was she so desperate to save Sherlock Holmes that she'd actually poisoned him, knowing full well that in doing so she'd sealed her own fate, was she that obsessed with Mr. Tall Posh and Cheekbones that she'd sacrifice herself to save him, of course she was, stupid, never forget how close you came to doing the exact same thing because life had become so fucking boring it wasn't worth dragging on and on)...

"Call them off." Molly's voice, so soft, so pleading. He saw her arm move, tracked her hand as she offered his own mobile to him. "Call them off and I can - I can stop this. Reverse it. You can be free to go your way, leave London, live whatever sick life you want as long as you leave us out of your games. Leave him out of your games. Call it off, Jim. Please."

"Reverse what, exactly?" he asked, fighting down the unpleasant - and entirely unwelcome - sense of panic that threatened to eat away at his control.No. "What did you do to me, Molly Hooper? What poison did you dose me with?" The panic receded a bit beneath the weight of his curiosity; despite his inability to move, despite the numbness encasing him, despite his absolute fury at being outwitted by this little nobody of a woman, he was also...excited. Yes, that was the word. Excited. Impressed. Oh. she would suffer for her affrontry, but really, it tickled his senses - of the dramatic, of irony, of humor, even - that he'd so badly underestimated her.

"Call them off," she repeated, and he rolled his eyes.

"Oh, Molly, don't turn boring on me again," he huffed. "Answer my question and maybe I'll think about calling it off. Can't make an uninformed decision, after all. That's just bad business."

She went silent; he wished his head was at a better angle, so he could judge her expression, take a more accurate measure of her resolve.

Finally she sighed and lowered the mobile, presumably letting it come to rest on top of them; at any rate, her hand was empty as she groped behind her to fumble for something on the bedside table. Ah, her own mobile, which she was now awkwardly working with one hand.

Curious, that; why not simply push him off of her so she could use both hands?

Come to think of it, why hadn't she pushed him off of her in the first place? Why keep in such close, surely uncomfortable, proximity?

Why hadn't she at least slapped some antiseptic creme and a bandage to the wound on her throat?

Even if he couldn't feel them, he was certain the hairs on the back of his neck would be standing at full attention as he pondered those questions.

With a sense of foreboding unlike any he'd ever felt in his life, Jim Moriarty struggled to look past Molly's arm, casting his eyes down toward their bodies as best he could.

"Jim." At the sound of his name he automatically looked back up, to see her mobile screen, with a picture of their nude bodies, obviously taken at some point after he'd - blacked out? Collapsed due to the poison or whatever she'd dosed him with?

His breathing became labored, shallow, his heart suddenly pounding in his chest as he took in the full horror of the image she was showing him.

Two bodies, his and hers. The video - for video it was, not a mere still picture - showed their faces. First hers, eyes wide open and alert but sad, so, so sad. No smile on Molly Hooper's lips. And none on his; his mouth was open, slack, his eyes closed, and there was something odd about his face, about how flat it lay against her chest, but before he could decide what was so disturbing about it - aside from the fact that he'd apparently been unconscious long enough for her to film all this - the angle changed.

Panned slowly, oh so excruciatingly slowly, to show exactly what horrific, impossible thing she'd done to him.

Showed their bodies close together; the fingers of her other hand resting on his shoulder, no, not resting on, but somehow merging into his flesh, as if they were a pair of melting candles puddling onto her bed together. His breath caught, his heart racing as the merciless images continued: their abdomens fused together, a partial glimpse of his rump, his thigh where it had been carelessly flung over her hip, his other leg next to hers...all melding, fusing together into one lump of pale flesh, two becoming one in the most literal sense possible, a sort of sticky sheen coating the exposed flesh, even the fucking toes on his feet now merging together into some kind of sick fucking hoof or something…

"Photoshop, boring," he snarled, struggling and failing to distance himself from her, from those disturbing, impossible images. Struggling and failing to convince himself of its unreality, its impossibility. "Or is it some kind of hallucinogen, is that what you gave me? Some drug cocktail to knock me out, immobilize me, make me see things that aren't fucking REAL?"

He screamed the last word, spittle flying from his lips; he saw her flinch back and smiled in vicious victory at having affected her so visibly.

It was nothing compared to what he was going to do to her, what he was going to have done to her. And to Sherlock and his three little pets. Fuck them all, no one put Jim Moriarty on the back foot, no one played him, no one tried such cheap, obvious tricks to try and control him -

He said all that and more, and all Molly did was just...lie there and take it. Oh, he heard a hitching breath now and then as he spewed insult after insult at her, but not once did she so much as attempt to move out from under him.

Not once, even when he heard her let out a distinct sob, saw the trickle of tears dripping down her chin to splash on her chest, did she push him away and run as her trembling told him she so desperately wanted to.

Not. Once.

"What are you?" he whispered as the vitriol and rage abruptly faded into nothing. As if his emotions, so extravagantly spent in that one, long rant, had been drained from him, leaving him as numb on the inside as he continued to feel on the outside. And his voice, was he whispering because he had no energy or was it because it, too, was starting to fail him?

Her response was entirely unexpected. "It's not an exact analogy, but do you know anything about anglerfish biology?"

His attempt at a shrug resulted only in an odd bob of his head. "Ugly buggers. They have little lights they dangle to lure in their prey. What else is there to know?"

"The females are larger than the males, much larger." Molly's voice took on a lecturing quality, the sort he normally tuned out, but which instead held him in a state of horrified fascination. "When the male finds a suitable mate, he bites her." She grazed her fingers across her throat, across the wound he'd given her, and sweat began to drip from his forehead. Surely his heart should be pounding in his chest right now, why couldn't he feel it?

"...latches on until their skins fuse together, until their blood vessels do the same." Molly was still talking. Explaining. He forced himself to listen to the rest, focusing on her words in order keep his mind from replaying those horrific images on her phone. "He loses much of his body until nothing is left but a pair of testacles which she can use when she's ready to spawn."

"Mmm, sexy," he mumbled, his voice sounding dream-like to his own ears - well, ear singular, he supposed, since the other one was now presumably nothing more than a lump of shared Molly-tissue, along with the entire right side of his face. If he could shudder, he suspected it would be one of those long, intensive shudders that racked one from head to toe and lasted a subjective eternity.

"Well, we're a bit like that, the women in my family," Molly continued on doggedly. "We don't know how, or why, it just is. Once you bit me, got your saliva in my blood, it triggered the Merge. But it's not too late, Jim." Her voice turned coaxing, wheedling. "I can still reverse this. Just call off your assassins and this can all be over."

Christ, was she back to that again? One track mind, this woman - or whatever she actually was. Not really human, but then again, he'd never really been human, either, so who was he to judge?

Jim Moriarty, Consulting Criminal, that's who. Time to remind her of that all important fact. "Don't lie to me, Molly-luv. Don't insult my intelligence that way. You can't reverse this, and we both know it. I can hear the lies in your voice." And he could, so clearly, as if her voice and its every subtle nuance was the only one he'd ever truly heard. As if it and her heartbeat, so steady beneath his head where it rested on her chest, were the only sounds that mattered.

Perhaps they were, he mused, considering they were literally going to be the last things he would ever hear.

It took her a moment to respond, and when she did it was soooo disappointing and predictable he could have recited it along with her word for word. "Then if you know the truth," she said, once again holding his mobile up, "make the call anyway. Please. Stop this. What's the point when you won't be around to see the fallout?"

"Sorry, Molls," he said, his voice weakening further as a weird sort of peace washed over him, so comforting in the aftermath of so much emotional upheaval. Calmness after the storm, a state he'd rarely felt. So refreshing. "No can do. I might miss the fallout, but knowing that you'll have to live with it? That's more than enough for me. And," he added before she could speak again, "don't try to feed me any bollocks about how this is killing you too. Because we both know it isn't. Your voice is strong, you heartbeat is strong, fuck me if you aren't stronger than I realized. Should've...should've known how strong you were when you kicked me to the curb. Course," he added musingly, "the curb was where I wanted to be once I was done using you, but I'd honestly expected more crying and less yelling. Guess I've...underestimated you...for the last ti…"

He fell silent, his eyes still open and staring at nothing, no longer seeing anything.

And Molly Hooper began to cry in earnest, because everything that happened next was going to be her fault.

Hand shaking, she picked up her mobile and looked at the time. He would be there, at the rendezvous point Jim had arranged before she'd lured him into her - failed, what a horrible weight to bear, that all this had been for nothing! - trap. Holding the phone close to her face, taking a deep, shuddering breath, she instructed, "Call Sherlock."

There was nothing to do after that but wait for him to answer - and pray to a God she only partially believed in that her impulsive actions hadn't destroyed whatever backup plans Sherlock and Mycroft had put in place.

End note: Everyone had ideas and theories about Molly's secret. I hope the dark truth of the matter didn't disappoint. A shoutout to gettingovergreta for inspiring this fic. Thank you to her and thank you to you all for your reviews and comments. Only a couple of (short) chapters left to go, including (possibly) an alternate ending because I'm feeling like a Halloweeny Meanie, hee hee hee!