As I'm sure some of you know, today, the 10th of July is Nikola Tesla's 156th birthday! So, obviously, I had to write smut to celebrate. Took forever and it's dirtier than what I'd have like (a touch dark too I think) but here it is. And inspired by a certain Sleepers quote. And a few from the season four deleted scenes. Nothing too spoilery though I hope :) Also might be a little OoC, I had trouble with the banter...

Many thanks to those on Twitter who kept me writing :P And a big happy birthday to DragonAceSg7 for yesterday. She almost, kinda shares her birthday with Tesla!

As always, I don't own this. I wish I did, but I don't.

xx


Nikola was bored. And tired. And lonely. And somewhat disgruntled. No one had made a single mention of his birthday all day. He hadn't been dropping hints or anything, refused to stoop so low but he'd expected at least one of the children to say something. Heinrich even had a copy of his biography tucked behind the messy desk in the corner, for heavens sake!

Even Helen had been terrifyingly distant all day, brushing him off with the cry of mountains of paperwork. He knew setting up the network underground would cut into the amount of time he'd have her naked and alone but it had been a week since they'd had anything more that a quickie in a closet and he was sick of it. They weren't an item per se but he was starting to get titchy.

Briefly he considered stumbling off to her office but honestly he was too tired to deal with her dismissive attitude at the moment. He'd been working on the faulty power packs for stunners ever since waking up cold and alone around 4am and all he wanted to do was down a few glasses of his vamped up vino. The effects didn't last very long but it had been a long time since he could get plastered for his birthday. In fact, the last he'd done it he'd ended up with his head buried amongst a mass of petticoats with Helen whispering sweet words of encouragement.

Maybe once drunk he'd go find Helen and at least get some pity sex. And he could bring an umbrella to tuck behind her ear. It was a suitably drunk and affectionate thing to do, he decided. He didn't have an overwhelming desire to see her face when she realised that she'd forgotten his birthday but he was fairly sure he could convince her to bend over the desk like they did that night when he'd first arrived down here. She'd come like a wild hellcat that night, practically howling as he'd worked her.

Nikola smiled at the memory as he rounded a corner. Pity sex wasn't great but he simply wanted to hold her tonight. He'd take what he could get.

He'd barely made it a few steps down the hall when he realised there was something off about the place. On the doorknob at the very end of the corridor was a silk scarf. Bright red, tied in a bow. On his door.

Pausing outside, he listened closely for a minute, frowning at the scuffling that he could just make out through the heavy door. Slowly he turned the knob, pulling the door open as he prepared to launch an attack on whoever had had the gall to invade his personal space.

He stopped short just a foot inside the door.

"Helen?"

Her eyes widened and she swallowed.

"Untie me."

Nikola simply stood there, too shocked for words.

"Untie me," she half hissed at him.

Reaching over, Nikola flicked the switch and flooded the room with light. It wasn't that he couldn't see, his vampiric eyes helped with that but the reality of finding Helen Magnus hand cuffed to his headboard was something that needed full lighting to properly digest.

She was lying in the centre of his bed, arms flung above her head while she fought against the bonds in a futile attempt at escape. More than that, she was rather scantily clad. She wore a tight, figure hugging chemise that just barely contained her ample breast before coming to a rather abrupt stop about an inch below her buttocks. Her legs were covered by sheer white stockings that reminded him of their early flirting when he'd gotten to experience a close encounter with thick stockings and masses of petticoats. Only these were significantly more modern. They were the stay-up kind, the tops of which were a frilly mass of white and deep red lace. And there was not a garter in sight.

"Nikola!" she cried angrily. "Shut the door and help me up!"

He wanted to help her, he really did but there was little more he could do than gape. She was sitting up for the most part which always showed off her body well, he thought and with her hands clasped the way they were over her head... Well, he'd never been happier in his life to have a slatted headboard. A slatted and tall headboard.

Her eyes were flashing dangerously and with each passing second her attempts at gaining release became even more desperate but as she huffed her breath upwards, blowing her bangs off of her face all he could manage was a soft chuckle.

"Nikola!"

Still chuckling, he turned and slowly closed the door. Once he was certain the lock was in place he turned and strolled to the foot of the bed with a wide smile.

Helen looked as if she were about to bite his head off but he couldn't resist whipping out his phone and snapping three quick little pictures. And then a fourth when her sweet little mouth dropped into a perfect 'o' of confusion.

After that he figured he had about three seconds before she broke his bed and strangled him with what appeared to be pink, fluffy hand cuffs.

But she didn't fly off the bed and she didn't have him pinned to the ground. She gave it a very good go but the cuffs were stronger than they looked. Or perhaps it was the headboard. Either way, she growled at him, jerking against the restraints.

"Now, dearest Helen, how are you?" he asked cordially, rocking back on his heels. In all honesty it was taking everything he had to not pounce on her this very second.

"Let me up already," she growled.

"Well, technically I didn't put you there so I don't think I'm under any obligation to let you up," he offered with a grin.

"You will let me up this very second or so help me, you will pay."

"Will I just?" he said with a chuckle.

She narrowed her eyes.

"My inclination to spend the night is suddenly waning," she said calmly.

Nikola merely scoffed.

"Considering how blasé you've been about such activities in the last week I have to admit, the threat does not faze me."

Her face fell at the words and he almost laughed. How could she not see straight through such a blatant lie?

"Now," he started. "Why are you cuffed to my bed?"

"Let me up and I'll explain," she almost pleaded, a tiny desperate note sneaking into her voice.

"I'd rather you did so now."

"Nikola..."

"Helen, I'm fairly sure I'm in control here. Otherwise you wouldn't be tied down, would you? So spill."

She huffed again and glared at him.

"It was an accident."

"A likely story."

"I hadn't intended to get stuck. Honestly, Nikola. It was a mistake."

He tapped a finger to his chin and grinned.

"There is more to it than that, darling Helen. Now explain. Properly. Or I won't let you up," he said, moving around the bed to sink down onto it.

She sighed and once more tried to break him with a glare.

"It was... it was supposed to be for your birthday," she muttered, not meeting his eye as she still tugged at the cuffs. "But I was waiting and I wasn't sure if the height would work with the cuffs so I... I figured there was no harm in simply testing it..."

"And?" he asked, distinctly amused.

"And your headboard is simply too high for this to be a pleasurable position," she finished, eyes darkening. Nikola's blood pressure rose a few notches but he worked to keep that fact off of his face.

"Did you not think that this could end badly?" he asked, voice just barely even and, based on the look in Helen's eyes, she was well aware that he was losing it.

"I dropped the key," she admitted.

He snorted at that, leaning back to once more soak in her appearance.

She was truly delectable, all long legs and skimpy lingerie. And it was for him. It warmed his heart as well as some other regions of his body but it also gave him an unpleasant thought. Quickly he scanned the room, looking for her clothing or at least something to indicate that she hadn't trekked down here in what she was wearing now. The path between their rooms was a relatively short one but it passed through some very public domains.

"Helen..."

"What is it now?" she grumbled.

"Can you please tell me you didn't make your way down here dressed in nothing more than that?" Or else I might have to jump you this very second. The thought of her creeping about in that attire made his blood pound furiously in both red hot lust and intense, burning jealousy that someone may have gotten a glimpse of his woman. It was a thought he knew she'd shoot him for having but he had no other way to describe other than 'taken'. By him. And he accepted no threats.

She rolled her eyes and jerked her head in the direction of the window seat. A gauzy white something lay pooled against the cushions. He could tell from here that the dressing gown was the most impractical garment ever conceived, the thing fabric allowing everything to be on display for whoever should catch a glimpse of her.

He noted absently a beautiful pair of heels by the seat too and recognised them for the advantages they would provide. The heel was so hellishly high that he could only imagine how painful it was to wear them but the thought was superseded by the memory of how her hips swayed when she wore such contraptions. They really did astounding things to her already delightful derriere.

"That was a very risqué run, Helen," he said, his hand creeping towards one of her ankles.

"I know, it was stupid," she grumbled, eyes downcast with what Nikola knew to be true embarrassment. As lovely as she looked in that moment, his heart throbbed a little painfully, forcing him to shuffle forwards and squeeze her calf.

"Not that I don't appreciate it," he added softly, almost shivering at the sensation of the silk stockings she wore.

Her head snapped up and she gave him a little smile.

"Let me up then?" she asked sweetly, her voice all melty and gooey and Nikola knew he'd been had.

"Tell me why you tied yourself up first," he challenged, leaning back. Anymore skin to skin contact and he'd give in, he was certain of it.

"I already said," she grumbled, going back to fiddling with the cuffs.

"Yes, yes, for my birthday but that doesn't explain why you thought it was a good idea to cuff yourself to my bed."

"Do you remember a few years ago? You made a comment..."

He frowned, not sure where she was going.

"We were saving you from those blasted teenage vampires."

"Oh."

"Precisely."

He tried to bite back a grin but he simply couldn't. Here she was, love of his life, Helen bloody Magnus, and she had tied herself to his bed. With handcuffs. In lingerie. If he didn't already think she was amazing, he would have now.

"I'd say that it's a sweet gesture but that's not really the right word, is it?" he joked, reclining slightly as she glared at him.

"Please just let me up Niko," she begged, blue eyes going wide.

"How long have you been here for?"

She bit her lip.

"I'd guess for almost two hours."

He burst out laughing at that, ignoring her angry stare.

"I wasn't tied up for all that time," she tried. "I simply got fed up with waiting."

"So you cuffed yourself to my bed?"

"I know!" she burst out. "It was stupid and reckless and childish! Just help me, Nikola."

Softening, Nikola shifted closer, reaching out to cup her cheek. His thumb brush across her cheek bone tenderly.

"Don't look so sad," he murmured. "To be honest, this is one of the most alluring things I've ever seen."

Her lips quirked in a small smile and he leant in even closer.

"In fact, you're bloody lucky I haven't jumped you already."

He watched as Helen's eyes darkened at the words and smiled, brushing their lips together chastely. For a moment they kissed sweetly and Nikola smiled, pulling back. Of course, his smile grew to a grin as Helen tried to follow him.

"Nikola," she moaned, drawing out his name.

"They're sex cuffs, Helen. Don't they have some kind of... safety latch?" he asked curiously, frowning when she flushed once more.

"Not sex cuffs then?"

"I may have modified another pair I had lying around," she admitted sheepishly. "I've been known to break the standard version."

Nikola held up a hand and made a face.

"No tales please. I can deal with the knowledge that you've been intimate before but details..." he shuddered.

"It's really a shame you didn't get to meet Charlotte," she mused, an evil glint in her eye. "I rather think she'd have kept you in line somehow."

"Do you want the cuffs undone or not?" he groused, pretending he didn't feel the prickle of arousal flash up his spine.

"Please," she said eagerly.

"Though it is my birthday," Nikola mused, tapping a finger against his chin. Helen's leg came up behind him, knee walloping him between the shoulder blades. Yelping he fell forwards, almost landing face first in Helen's cleavage.

"Horrible woman," he muttered. "I thought you were supposed to be nice, considering this was supposed to be my present and all. And you've been horrible all week."

"I was trying to make tonight special," she said adamantly, obviously seeing the small pang of hurt he tried to hide. He knew she'd have her reasons and couldn't really complain seeing as they'd still gotten plenty of action but he liked sleeping with her. He like to make love to her and wake up with her nose against the back of his neck. He like her and he hadn't had nearly enough her time in the past seven days.

"By tying yourself up?" he asked, trying to get back to the joking.

Her lips quirked into a small smile.

"By spending the night with no distractions, just us. This way I can't run off at dawn, can I?"

This time it was his turn to smile. Over the years it had been her trademark move, the whole disappearing act. From Peru to Vienna, she had always managed to slip from his arms just as the sun rose and before he could wake up to truly do anything about it. Now, that wasn't so much of an issue most days but she'd caught his frantic scramble for her warm body one morning and though they hadn't spoken about it in depth, the small panic attack he'd suffered upon waking had probably clued her in to more than he'd have liked. She'd gotten all introspective for nearly 36 hours and it was only with a very thorough make-out session that quickly turned into a memorable afternoon hidden among the stacks of the dark corners in the library that she had re-emerged to him with a smile.

He smiled at her, pressing a delicate kiss to her lips. He understood what she was saying. They weren't that good at words and talking and the like but he knew.

She was promising to stay.

Nikola shifted slowly, his body hovering over hers.

"Where's the key?" he breathed, their faces only centimetres apart. She blinked up at him hazily for a moment, clearly confused.

"B-behind me."

He snickered against the skin of her throat, trying to keep a clear head as she began to arch up beneath him.

"How did it get there?"

"Dropped it," she panted. "Nikola..."

"Where is it?" he asked, pulling back. She frowned up at him.

"I'm almost sitting on it," she tried and he smirked.

"I don't know where you mean, Helen," he singsonged and she almost growled, legs shifting to try and tug him closer.

"Nikola, enough of this. I want you."

"And I want to know where the key is," he countered, running his hands up and down her thighs. Helen groaned, eyes fluttering closed as she raised her hips off the bed.

"Where is it?"

She half whimpered, biting her lip to keep the noise in.

"Just..."

"Where?"

"Behind my arse," she burst out angrily. "Now hurry up an-." Her protest turned into a squeak as he grabbed her hip, pulling her body flush against his.

He was fed up of the game, teasing was good but now he needed her. Focusing for a moment, he unfastened the cuffs, enjoying the way Helen almost melted into him. Until, that is, she used her entire body to force him backwards and to the side.

He fell off the bed with an unattractive humph, his only saving grace being the fact that he managed to drag Helen's scantily clad form down with him. And her grunt was significantly less dignified than his.

"What on earth are you doing?" she cried, trying to fight off his arms but Nikola held her tight.

"You pushed me off," he replied easily, "what did you expect me to do?"

She growled before finally scrambling from his grasp, standing on shaky legs as she glared. Chuckling, Nikola heaved himself up, panting slightly.

For a moment neither of them moved, simply glaring at the other warily before Nikola could take it no longer and launched himself at her.

It wasn't his fault, really. She was all dishevelled and pretty much naked and he could still see that shiver of arousal in her posture. And he wasn't disappointed. The second he had her in his arms, her body was pressing forwards, their mouths meeting furiously. Hungrily they clutched at each other, Helen's nails digging into his shoulders through the thick fabric of his jacket and dress shirt.

Grabbing her arse, he walked her backwards, half tossing her onto the bed before following her body with his own. Her arms and legs wrapped around him as her lips sought out his once more. Together they worked at undressing him, almost tearing at his pants while her nimble fingers fiddled with his tie.

When finally they both gasped in a few scant breaths of air, Nikola tried to pull back only to have Helen follow him eagerly. She tried to pull him down again but he fought, grabbing her wrists and pinning her to the bed.

Her eyes darkened as she again fought to capture his lips but he merely smiled, a plan he could comfortably classify as one of his more genius ideas forming in his head. One hand still holding her wrists, he threaded his other arm around her waist and hauled them up until their hands came into contact with the headboard.

Helen's eyes widened but before she could comment he sat up, releasing her as he frantically pulled his tie off. Helen sat up, frowning at him as her hands moved to relieve him of his jacket and then shirt.

Her hands roamed his chest as he leaned in for a kiss, cupping cheek tenderly while his free hand groped around for the cuffs he knew were nearby. He smiled into the kiss as he felt her hands move for his belt and only when her fingertips brushed across the fabric of his underwear did he pull back and take her hands.

Before she could protest he took his tie from where it lay discarded beside them and wound it tightly around her wrists. By the time she started to fight him, it was too late.

"Nikola!" she cried, tugging on the bonds. "What the hell do you think you're playing at?"

Chuckling darkly he pulled her bound hands above their heads, pressing his body against hers until she was lying back against the thick quilt.

"You were the one who tied herself to my bed," he reminded her, letting his lips ghost over that spot just beneath her ear. For a moment he simply lavished attention on the delicate skin, holding her wrists down until she was panting and squirming against him with her legs wrapped around his in a vicelike grip.

"Tell me when," he whispered against her neck and he heard Helen swallow before nodding once. They'd played games like this before and they both knew the rules.

Pulling back, he watched as she began to struggle once more, arching up in an attempt to break free. Nikola grabbed the nearby cuffs and latched them through the loop he'd left in the tie before reaching down to secure it to the metal bar running beneath the slats of his bed. All together it was just long enough, Helen's hands resting against the base of the headboard.

"Very fifty shades," she murmured as he admired his handiwork.

"Pardon?"

"Nothing," she said, shaking her head. "Just a book."

"Oh I know it's a book," he countered, one hand resting on her hip. "I'm just amused that you've read it."

Helen rolled her eyes so he tightened his grip on her hip in warning. Her eyes flashed and he caught the ghost of a smirk roll across her lips before she schooled her face into a carefully blank expression. He smirked.

Smiling down at her, Nikola ran a hand up and over her breast, letting his fingertips brush one tight nipple before tracing faint patterns on her collar bone. She swallowed and tilted her head back, exposing more skin to his caresses. For a moment he lost himself in the feeling, simply watching as her body reacted to tiny nuances in his caress.

Finally he pulled his hand away, blinking to try and focus once more but it was useless. Her skin was flushed and her breath slightly laboured and he just wanted her.

Fighting off the majority of his transformation, Nikola used his strength to tear the flimsy fabric covering her out of the way. It split effortlessly, sliding apart to reveal what he'd already begun to suspect. No underwear.

He steeled himself, pulling back and tugging off his remaining clothes as quickly as he could manage before hurrying back to kiss her thoroughly. Helen responded as she always did, with an enthusiasm that never failed to ignite him. His hands were flying across her body roughly, memorising the feel of her as she panted and whimpered into his mouth.

"Niko," she breathed. "Niko, Niko, Niko."

He merely groaned in response, his body temperature rising as she rocked against him, teasing them both as her legs tried to hold him exactly where she wanted him but he still held some power over his limbs and pulled back, content to watch her struggle and growl at him for a bit.

Carefully he threaded a hand between them, rubbing at her heated centre in small, teasing strokes he knew would only make her angrier at his reluctance to bring her the release she was close for. If this was his birthday gift, he was going to milk it for all he could. So long as he could hold out.

She smelt divine, the pure scent of her wreaking havoc on his senses. Working for some higher brain function he leant back down, taking a nipple between his lips and sucking hard. She cried out inarticulately as she jerked at her bonds. A few stray curse words slipped through her lips as she began to pant, hips rocking against his hand before the words turned into strangled moans.

His lips slipped from her breast, down its curve to where sweat was beginning to pool and he licked it away before moving to bury his nose in the crook of her neck. Breathing deeply he let her sweaty scent wash over him as her heated pants increased in volume, making his blood pound with desire.

In a very smooth move he hadn't expected to work considering his inability to think straight, he shifted smoothly, removing his hand as he slid into her depths. Her entire body shuddered and a few curses of his own slipped through his lips.

"He-helen," he croaked, head resting on her collarbone. It had been too long since he'd been here, like this, with her. He was so close to losing it as she groaned into his ear that he briefly considered giving in and coming on the spot.

Only when her hips surged against his did he remember why her nails weren't clawing at his back, urging him to move already. She was tied up Under him. At his mercy.

Swallowing heavily he sat up a little, focusing solely on that look in her eyes. It was one he'd seen a few times, back in Peru for one. That night had started in a similar fashion to this only it had ended with her disappearing before he'd woken. His gaze flicked back to the bindings holding her in place and he smiled.

With a new resolve, he sat up properly, wrapping her legs around his waist before picking up a relentless pace.

Helen's eyes widened with the first thrust, a small cry slipping from her lips as he pounded into her, hard and fast.

"I'm going to make you scream," he promised, voice low and rough. She bit her lip but said nothing, simply thrusting back in time with him. Well, as much as his tight grip would allow.

He felt like he was burning up from the inside, sweat beading across his back as he took her with everything he had. It took a lot to make him sweat though he couldn't focus on the fact, only the fire that was eating at him.

Helen was moaning freely now, her body writhing and shuddering with each deep thrust. Nikola was grinning manically, entire being focused on the sweaty, shaking woman who was murmuring his name.

And then her eyes grew wide, her body tensed and Nikola just about saw stars. Dimly he was aware that she was practically screaming her release but he was too caught up in his own to truly acknowledge the fact. It was like his world narrowed, the edge blurring until all that existed was Helen's body as it clamped around him.

With one last half-hearted thrust, Nikola slumped over, his entire body drained of all energy. Helen was panting beneath him, their sweaty bodies cooling far too rapidly but there was nothing he could do about it. It took Helen's constant muttering of his name to finally grab his attention.

"Niko, the tie. Please."

With a weak arm he reached up at slit the binding with a talon, the brain function for more than that still beyond him.

Helen's arms slowly came down around his shoulders, holding him with trembling hands.

And then he felt her tighten around him.

Nikola groaned.

"If I'm going to be sore in the morning," Helen breathed, heart still racing, "then let us make it worthwhile."

Nikola merely groaned again, feeling himself begin to harden beyond all reason. Silently he thanked his vampiric ancestors for their numerous gifts before grabbing Helen and rolling, landing with her on his chest.

Carefully she propped herself up, hands planted on his chest as her sheath fluttered around him once more.

"You... are... evil..." he growled out. He could see the exhaustion he was feeling in her body too but as she began to move shakily it began to fade.

"Happy birthday, Mr. Tesla," she said huskily, eyes darkening once more.

Yes, he thought to himself as pleasure fought against the aches and pains of their recent coupling, yes it was going to be a very happy birthday indeed.