Any possible warnings: Collars, Handcuffs/chains, Seems dub-conny but isn't really, BDSM-ish, D/s, fem!dom

There was a soft knock at the door that had Nat's attention in a heartbeat. It wasn't often that she got visitors, especially when many of the others were out on dates for the insipid holiday themselves. Valentines day held little ceremony or special meaning for her, and not having been one to celebrate it she often requested missions specifically to get away from the other happy couples. Not that she really minded it, having to deal with them generally 364 other days in the year, but for one day she would've liked to just be with her thoughts, a bottle of vodka, and with a man caught in her cross-hairs, the thrill of a successful mission thrumming in her veins. To his displeasure, Fury had told her that for once the bad guys seemed to have been taking the day off. Bastards couldn't get anything right.

So when the knock came, and Jarvis alerted her to Thor having arrived with a present for her, she had to admit she was wary as all get out. How was it that Thor, of all people, knew about the holiday, anyway? And why wasn't he out with Steve, who she thought had dinner plans for them? She moved over slowly to unlock the door, stepping backward as he stepped inside.

The question of what he was doing there died in her throat when she saw him all but dragging his little brother behind, a large red bow tied around his chest, the manacles and collar attached to the gag clinking with every step. He had murder directed at his brother in his eyes, though they softened slightly as he looked over at Nat, who had to admit that her breath caught in her throat. Oh. Well then.

"What the hell are you doing, Thor?" She demanded, looking from Loki to the beaming blond man, who just chuckled.

"I thought you might like a Valentine's day present-Steven tells me that this is a momentous day for lovers to spend together. Perhaps you might like my brother to spend the evening with as you choose," he said with a wink. She nearly choked on her surprise, eyes wide. What?! She'd been very discreet with the looks that she'd given his brother-especially when he'd been brought through the first time in the same shackles that now held his wrists together. Sure she'd had to clench her legs a little tighter and excuse herself earlier than the rest of them that evening, and certainly her orgasm had been mind-blowing with the same imagery of him in those cuffs between her legs, his tongue-.

But no. She'd been careful. She'd been cautious. She'd kept her face collected and kept herself from getting far too interested in the goings on of the trickster god that now presided within Stark Tower, rubbing elbows with the very people that put him there.

Besides she was certain that she, of all people, would be hated above all the others. She alone had defeated him at his own game in the imprisonment chamber, had revealed his plans, had shut down the tesseract with the help of Selvig. He had every reason to hate her most, and as Thor wasn't normally a cruel man, she couldn't imagine him bringing his little brother to her in such a state just for her enjoyment.

Which could only mean-.

She took quick stock of him, schooling her face, watching how his cock had already hardened in the black leather pants he refused to part with (not that she complained), how his chest and throat were flushed yet his eyes were slightly glassy, and still hard, as if he was trying to hide something from her. He'd never been very good at that.

Whoever said Thor was a bumbling oaf clearly needed to get their own competencies checked out.

She allowed a smile to curl her lips as she took in the way that Loki's hands seemed incapable of staying still and relaxing as they fell to his lap, Thor offering the chain that connected everything to Natasha, who took it with a steady hand and watched as Thor left after another wink.

"Treat him well! Steven and I will be out for the rest of the evening, as are the others. Have fun you two," he sing-songed. He'd been hanging out with Stark for far too long, picking up on his mannerisms already. The silly man. Nat waited until he'd disappeared out of her door before asking Jarvis to lock it and turn off all security cameras in her room, only having been activated because of Loki's appearance, overriding any objections the AI might've been trained to have with a code of her own. Having worked for Stark in the past had really paid off. She moved forward towards the chained god, grasping the edges of the gag and pressing into the locks with her thumbs to undo them, hearing him gasp softly as it was removed from his mouth.

She started talking before he could even think about it. "Now, we've got a couple of ways to play this out," she said, her eyes meeting his. "I'm not interested in forcing you to do something you wholeheartedly don't want to, so if Thor misread you-." Which she doubted. Thor would never intentionally put his brother into a situation like that without some kind of backing up logic. "Then you have five seconds to tell me that you want to leave. I'll take all these off and we can pretend this never happened, and nothing will come of it. Ever."

He paused, opening his mouth in the silence, and for half a moment she really thought he was going to say he wasn't interested. It seemed that curiosity and lust, however, stayed his tongue and he promptly shut his mouth again. Good. She let out the breath that she didn't know she'd been holding and stood on her tiptoes to press her lips hard against his mouth. They were chapped, yet the kiss was wetter than she'd expected, likely from him having been gagged for so long, but his technique was refined as all get out, she had to admit, and before too long she felt him pressing hard against her, his hands shifting to try and move around to grab her without having to break the kiss and without pulling at the collar. She grinned and pulled away, glad to hear the soft keen of disappointment leave his lips, before she grabbed the collar and tugged on it. The hiss of pain and the jolt of his cock against her thigh told her she wasn't far from the mark.

"You're mine tonight," she growled, her eyes meeting his. "All mine. Understand?"

He searched her gaze, though what he was looking for she couldn't tell, and the corners of his lips turned upwards. "Should I call you madam or mistress?" He asked, velvet wrapped voice a little shakier than normal.

"Madam would work nicely," she assured him, smirking, before taking the gag and throwing it to the side. They'd use it later that night, she supposed. He was just as pretty in the rest of his chains, she thought, pressing her thighs together as she felt the familiar heating sensation grow ever stronger. It was all too perfect. She had to move away to get a decent amount of mental distance from the situation, tapping her finger tip to her lips as she surveyed him. Where the hell did she want to start? The bow around his hips was promising, red as Thor's cape and just as soft. He wore trousers on underneath it, as well as a plain green shift, but she grinned to see that when she unraveled the bow the rest of his clothing disappeared. Not a bad trick at all. She took a slow breath before pushing him backwards with a hand on his bare chest, waiting until he toppled backwards onto the bed. His cock was hard and leaking, bouncing slightly with the motion, and she drew her tongue over her bottom lip. Hmm. Where did she want to start? With a slow hand she dragged her hand up one of his legs, skin soft as she trailed her fingertips over his upper and inner thigh, watching as goosebumps prickled his pale skin.

"How long have you wanted this, Loki?" Nat couldn't help but grin, looking up at him as she took her time wrapping her fingers around his cock and giving it a slow, hard tug. His back arched slightly. "How long did it take for you to plant the idea into Thor's head that I would appreciate an offering such as this?" She kept herself from grinning, but just barely.

He rolled his eyes, as though to say it wasn't as though she hadn't wanted the same thing. She'd give it to him, he was good at reading her. Not as good as she was him, but decent she supposed. She just gave a low laugh as he groaned when her hand stopped its movements, trailing upwards as she drew her thumb over the tip of his cock. The strained flesh pushed towards her, a whine leaving Loki's throat in a rush, before Nat pulled her hand away.

"How long?" She repeated.

"Since the Helicarrier," he said quickly, velvet words a jumble as he moaned when she took him by the cock again and stroked him slowly, reveling in how thick he was. She couldn't wait to find out how good he'd feel.

"Oh? You liked it when I beat you, did you?"

He didn't respond, his hips pushing upwards into her hand. She pulled away as a response and he let out a low cry of disbelief.

"I liked your intelligence. Your fire. No one's ever done that to me before," he admitted, eyes slamming shut as she bent over to take him in her mouth this time, swirling her tongue around the tip.

"What more?" She asked after pulling away with a lewd pop, echoed by dismayed shouts from the man beneath her. She could feel her core pulsing between her legs, begging for some of her own tension to be released, but took a deep breath to calm herself down. Control. She needed control over the situation.

"I wanted to see if your mi-ah!" He tensed as she took him into her mouth again, pausing until he started talking more. "Wanted to see if your mind was the most fascinating thing about you. How long it would take you to unravel any of my other plans. I liked that you discovered what made me ti-oh Norns, please Natasha," his back was bent again, trying to push deeper into her throat, but her will was absolute, and though she dragged her tongue lazily over the head again, tonguing the slit at the top, she didn't give him the full pressure and attention he craved. No, that was reserved for when he was inside her, which wouldn't be long. She wasn't sure how much more she could hold out.

"You've got a thing for intelligence, do you?" She purred when she pulled herself off of him once more. His displeasure was cut short when he saw her disrobing, his eyes growing wide at the sight of her exposed breasts and creamy skin as she pulled her sweater up and over her head, throwing it to the ground, followed shortly by the SHIELD issued sweats she'd been lounging in. She'd decided against wearing panties and grinned when she watched him subconsciously lick his lips.

She shifted him further onto the bed before moving closer to him and positioning herself just above his cock, his flesh seeking hers as she gyrated her hips teasingly, hands taking her breasts and squeezing, as though Loki wasn't there in front of her.

"Beg me for this, Loki," she said. "Tell me how much you want me. How badly you want to feel me. It'll be the last chance you get, and if you do it well enough I'll let you come. You don't, and I'll use you until I get bored," she grinned.

He didn't waste any time, sitting up quickly to press his lips to hers, the chains around his wrists and throat jingling as he submitted to her willingly.

"Please Natasha, please fuck me. I need you atop me, I'll do whatever you wish," he promised, last word cutting off when she grabbed him by the hair and tugged his head back, her eyebrows rising.

"Beg."

His face hardened, clearly not what he'd been expecting.

"Come on, silvertongue. Beg me to fuck you, to take you as my own and make you mine. What'll you do if I decide to?" She teased, her free hand moving down his chest, tweaking his nipples until they hardened and he lost his breath.

"Nata-ah-sha, Natasha please. Please fuck me. I'll do whatever you want, say whatever you wish-," he gasped, the tip of his cock pressing inside of her as she allowed herself to shift an inch down. "Pleasepleaseplease," he finally begged, kissing her jaw, throat, collar. "Natasha, I'm all yours. All yours to fuck but please don't tease me any longer. I can't take it. Prove to everyone else that I am yours, my darling."

That was it. She gasped, having teetered on the edge of giving in for the last couple seconds, before eventually pushing him backwards until he hit the bed and sinking herself fully onto him in one swift motion. He shouted in pleasure, hips bucking up into her so that she was entirely filled to the brim, their hips touching, and without further pause she started rising and falling atop him. One of her hands pressed on his chest as she lifted herself on and off of him, groaning at the sound of their slick flesh meeting and the feeling of being utterly and completely filled, the pleasure overriding her brain. He kept up a litany of words she couldn't understand mixed with her name until she wished to make him work harder and gagged him once more.

"You make such a beautiful slave, Loki," she murmured. "Slave to your pleasures, and now to mine. Do you like that?" She purred.

He nodded, mute, eyes wide and more vulnerable than she thought she'd ever seen him. It only made her groan and fuck him harder, sure that she'd bruise her hips from how hard she was fucking onto him. Her one hand moved from his chest to grab at the chains that kept him prisoner and tugged him up by it, kissing the gag hard as she kept him taut and on the edge, adoring how he trembled within and around her.

"All mine, Loki. Mine. Come for me," she ordered when she pulled away, eyes hard and her own orgasm just seconds away. But no. She wasn't going to be the first, wasn't going to weaken before he did.

He, at least, didn't have any problems with it, and spilled into her with a shout that was hardly muffled, eyes fluttering closed as he spasmed within her, setting off her own orgasm as she screamed and pushed herself even faster, losing all sense of rhythm and just chasing her orgasm until she was certain it might never end. He fucked her through it, whining and trembling even after she'd let him lay back down again. He looked wrecked, hair a great mess, eyes glassy and cheeks tear-stained from how intense his orgasm had been. She grinned and leaned down to kiss his cheek.

"We're just getting started, Loki. I hope you aren't too tired yet."

A thrum of excitement started once more in her stomach as she felt him stir within her, eyes lighting up at the proposition.

Best Valentine's gift ever. She owed Thor big next year.

A/N: Breaking the mini-hiatus for VDay-thanks for reading and hope you all have a wonderful valentine's day!