Disclaimer: All rights and characters belong to Chuck Lorre and CBS. Nothing is mine but the creativity and storyline.

WARNING: Mature adult physical scene. *hehe*

Early the next morning, after a good night's rest, Sheldon is pouring over his whiteboard with a cup of warm cocoa. His equations made sense but the overall math somehow didn't add up. It was suggesting that perhaps dark matter didn't exist. But that would be impossible; dark matter had already been proved.

Sipping his cocoa and furrowing his brow frustratedly at his work, his thoughts were interrupted by a light tapping on the door. Not taking his eyes from his board, he called, "Come in."

He still didn't look when Penny peered in through the door, and only turned to face her when he recognised her voice.

"Hey, Sheldon." She greeted warmly, still halfway out in the hallway, only her head appearing sideways in the doorway, "Have you got a sec?"

It was then and only then when he became aware that it was almost 9am and he was still in his pyjamas and robe. Setting down his cocoa and hugging his robe around his chest a little tighter, he turned his back completely on his board and nodded absently in answer to Penny's question. "I suppose. But it doesn't really matter, considering you were planning on coming in anyway, so my answer being either a yes or a no would be completely irrelevant."

Smiling politely, barely understanding, Penny simply said, "Yeah... OK," and stepped completely into Sheldon's living room, closing the door softly behind her. She was wearing only the white tank top she'd slept in that night and some pink 'Hello Kitty' flannel shorts, accompanied by a matching pair of fluffy pink slippers. Her hair was still damp and loose from that morning's shower, and she seemed to glow in the morning light.

It was only then when he realised how well the natural colour of her tanned legs blended with her light-blonde hair, which looked more honey-blonde with it's dampness. And he also took into play how long and slender her legs were, and how the perfect curve of her hips lead up to her slim waist.

He thought these thoughts to be indefinitely strange on his part – he'd never thought of Penny that way before – but had no more time to speculate on them because Penny began speaking.

"Listen, Sheldon, I just came over here to thank you again for what you did for me yesterday." She nodded her head absently, a kind smile playing on her full lips.

Sheldon said nothing, but held her emerald eyes onto his. He was fascinated by how suddenly they were latching onto one another, after at least three years of nothing. They'd certainly spent enough time staring at each other – even if it was most of the time glaring – but why was he feeling different about it now? What had changed? To his recollection, nothing in particular. But perhaps Penny thought so, and that was why this was happening.

No matter the reason, it didn't stop him thinking about how flushed her cheeks were, how full her pink perfect lips were, and how amazingly green her eyes were.

"That was really kind of you," Penny went on, drawing him back down to reality. She took a small step forward, and Sheldon mimicked her actions, partially unaware of what he was doing. "And I just wanted to say thank you... Again." Penny breathed a laugh, indicating her anxiousness.

"Umm..." She went on, taking another step forward. Sheldon did not move this time, and stayed routed to his spot, as his eyes did onto hers, "...I'm also sorry I made you miss work yesterday, too. I don't know about your boss but mine was pretty peeved," She breathed one more awkward laugh before half-turning herself back towards the door and concluding quietly, "Well... I, um... I better go."

Sheldon nodded once. "Of course. And I accept your apology, Penny. It wasn't really your fault." He restrained from mentioning the 'check engine' light once again, even though the little voice in the back of his mind was screaming at him to do so. He clenched his jaw and blocked it out, and managed a small smile which Penny returned before exiting the apartment.

As soon as the door closed, Sheldon exhaled so hard it was almost as though he'd just resurfaced for air during swimming. Of course, he'd never actually been swimming and refused to go in the water but that wasn't the point.

The point was: the smell of Penny's shampoo momentarily lingered in his nostrils.

He snatched up his cleaner-cloth and wiped the dark matter hypothesis from the board, wasting no time in scribbling a new one...

Knock, knock, knock.

"Penny?"

Knock, knock, knock.

"Penny?"

Knock, knock, knock.

"Penny?"

Penny would have answered instantly to Sheldon's distinctive knock if it hadn't had been nearly 1am. But she wasn't actually sleeping at the time; she was sat up on her couch watching a movie. She'd just picked it at random from the rental store, and wasn't really paying attention. She was sat daydreaming, pondering about things... about people.

It took her a second to stand up and fumble her way to the door, but when she answered she had to blink a couple times to adjust the light. She looked up and saw little crescents forming in Sheldon's ocean eyes from the moonlight streaming in through Penny's blinds.

Despite her sluggishness to answer it, Sheldon seemed surprised. "Oh," He began, his tone quite awake for 1am, "I hadn't expected you to be quite awake at this hour. I'm sorry to bother you, were you sleeping?" But he didn't need to wait for an answer, because he peered in through the doorway and saw the glare of the television reflect in the dark room.

"No, I couldn't sleep." Penny told him, stifling a yawn as to not back-track on her own statement. She leant against the doorframe and looked up at him, studying his features.

From his long, slender neck to the curve of his jaw line, the smoothness of his nose – not too big, not too small – until meeting his stunning blue eyes and drawing a breath back for them.

"What's up, sweetie?" She managed, her chest retracting from letting out a long sigh. What had brought all this on?

Sheldon shrugged absently, "Nothing. I just wanted to check you were alright."

Penny was a little confused, but shook her head a little. "Umm... Sweetie, why aren't you sleeping?"

He shrugged once more, as if it would be obvious. "I couldn't sleep, either." He answered simply.

After a pause, he continued, leaning onto the doorframe so he was closer to her face, lowering his voice dramatically, "Uh... Penny?"

The small proximity they were apart from each other was making her anxious, and she was finding it even harder to breathe. Forcing her eyes up so she would not look at his lips, she answered with a, "Yeah, Sheldon?"

But he didn't answer her straight away and follow through with his initiated conversation. But she did notice his eyes flit for a split second to her lips and back up to her eyes again. It was just for a split second, but she saw it. She knew for a fact she hadn't been imagining it. Only question was, why was she feeling weird about it? Almost if she wanted him to look at her lips...

"I have a problem I know only you can solve," Sheldon continued, his cheeks flaring at the slip of the eye. He preyed his voice stayed steady and in the darkness of the hallway Penny didn't notice his flaming cheeks.

Penny shook her head, both answering Sheldon and trying to knock out those strange thoughts from her head, "Oh, no, sweetie, you know I'm no good with all that scientific mumbo-jumbo–,"

"First of all, Penny," Sheldon interjected, wringing his hands out infront of him, looking to the floor and not at her anymore. He wasn't able to bear the intensity of which those green eyes were looking at him with. "Science is not 'mumbo-jumbo', as you called it, but work of men and women done over generations of years. Because of science we now know most of the mysteries of the world, not to mention how the world became to be in the first place – the big bang."

When Penny didn't answer, he looked back up to her and shook his head a little, "But that's not the point. The point is, this problem I've been having really has been annoying me."

Penny sighed, "OK," She told him, giving in, too tired to argue, "What's your problem?"

Sheldon visibly hesitated. His mouth opened to say something, but he then clasped it shut again. He kept gawking like a goldfish out of water, and Penny stared at him like he'd gone crazy, impatience running over her. When his left eye started to twitch, Penny had to say something.

"Sweetie, it's 1am. Can't you just tell me and get it done with? I'm really tired."

Sheldon sighed and looked to his shoes. It seemed to help, not looking at her face, because he started explaining his problem, "I've been having some difficulty with something I've never encountered before. It isn't new to me, I've seen it lots of times before, but now that it's happening to me I'm not so sure how to go about expressing it. You know better than all others that I have a history of saying things that, not necessarily that I don't mean or aren't the truth but, definitely something not to be said in a social convention. I'm afraid that if I try to explain this I will say something offensive to the one person I would hate to offend."

He was blinking down at her now, waiting patiently for her answer, even though he didn't quite explain himself properly. He seemed almost nervous to, but Penny shook her hair to show she didn't understand.

"Sweetie, I really have no idea what you're talking about. But if you're talking about expressing yourself, have you ever heard the saying 'actions speak louder than words'?"

"Hmm..." Sheldon pondered, looking off into space. As he thought about it, he supposed it would be a valid way to get his point across. He looked back down at Penny, a smile across his face. "Thank you, Penny, I think you solved my problem."

Penny nodded absently, letting her heavy eyelids hood over her eyes, "Happy to help," she told him drearily, slowly backing away to close the door.

But he stopped her, by stepping into her apartment and closing the small space between them. They were now inches apart and before she could ask what he was doing, he cupped her face in both his hands, leant down, and kissed her.

It was just one little peck, short and sweet, but it was still a kiss, as brief as it may have been.

Now, Penny had kissed a lot of guys, she knew she had. But never before had she experienced a kiss quite like Sheldon's. Of course, it was just a peck, so she couldn't draw too much onto it, but it was the way the kiss made her feel. It felt right, like it was meant to be. It made that empty hole in the middle of her chest close up like he was filling it. It made her toes curl and the hair on her arms stand on end. It ran a current around her, a current so strong, it couldn't not have been there.

Before she could follow through any further on any of these feelings, he pulled away, bringing his hands back down to his sides.

She gawked up at him, her mouth falling agape. He didn't avoid her gaze like she'd expected him to, but he did squirm on his feet and wring his hands out some more.

He opened his mouth to say something – most likely to apologize – but Penny cut him off when her lips came crashing down onto his.

Without any prompt, she deepened the kiss by wrapping her hands around Sheldon's neck to draw him closer. There chests were now touching and she figured she was standing so close she would be able to feel that thing happening. You know; that thing that happens to a guy when he kisses a girl.

It took a moment, but Sheldon followed through with the kiss, bringing his hands up to her hair and delving his long fingers into her shiny, coconut-smelling curls. He was close enough to her now to enjoy the full integrity of being able to just smell her. Not to mention kiss her, and have her kiss him back the way he wanted her to – the way he needed her to.

When her tongue traced his lips, he took this as a sign to open his mouth a little more as he kissed her. He drew his tongue out, too, and soon they were dancing together. Their tongues, not them as actually people.

He had no idea what he was doing, but he really was trying his best. He was trying in a way he never thought he'd try for a woman, trying merely to please her. To please Penny.

He thought for a moment, and if tonight went the way Penny's body language was indicating it would, he realised he would share a first everything with this woman. He'd already shared with her his first kiss and perhaps he would share his first sexual experience with her, too.

He could tell by the way her hands clawed at his face and ran through his short, dark hair that she was growing impatient. Even by the way little groans kept escaping her throat when their lips parted and they surfaced for air, he knew she wanted him.

Him, of all people.

He took a moment to thank God for how lucky he was at this moment (even though he didn't believe in luck and passed it off as hokum, and wasn't actually a squeaky-clean Christian like his mother wanted him to be) and bent Penny backwards momentarily so he could hook his hand round the back of her knee and bring it up around his hips so their pelvis' ground together.

It was an action based entirely on impulse, brought on by his male sexual craving.

When Penny surfaced for air this time, Sheldon brought his head down and kissed tenderly all along her jaw line, going down, down her neck until at her collarbone, and nibbling at the skin just below there. When Penny moaned a little at his nibbling, he decided to experiment some more and lay a single, flat lick on the hollow of her breasts.

The noise that left her mouth then almost took over him, and he lifted Penny's whole body against him so her legs were wrapped round his waist, stumbling straight into her apartment and shutting the door with a swift kick behind him.

He just stood in the middle of her living room, holding her against him, looking around absently. What to do next? Penny's eyes scorched into him, and he was sure if he met her gaze he would die of embarrassment – even though that was physically impossible. Who was he kidding? He didn't know what the hell he was doing. He couldn't please Penny; he couldn't please anyone but himself.

Letting the sorrow of it all overcome him, he must have made a face reflecting it, because Penny took his face gently in her hands and forced him to look at her. He had to oblige, but immediately wished he hadn't.

She was staring at him, just staring. She wore no expression, negative of positive. Not a word left her lips, and she didn't hop down from him. She just let him hold her easily as he stood there, gazing at her. Her eyes were wide, but not wide enough to show shock. It was as if she was communicating through her eyes, trying to tell him everything she'd ever wanted to. Like telepathy for the eyes.

Up until the moment she gingerly wiped her thumb across his cheek and he felt the warm liquid spread across his face, he hadn't realised he was crying. Even if it was just one single tear, it said so many things. It meant so many things.

"Don't worry," She whispered, edging her face down closer to his, "We belong together." And at that, she kissed him.

It was just one little peck, short and sweet, but it was still a kiss, as brief as it may have been.

And as he smiled up at her, slowly walking over to her bedroom, he pushed aside everything he'd ever known. From this moment, there was no more science. If science had a coffin he would make a headstone for it – science was 'dead' to him right now. There weren't any silly little tiffs, no three-strikes-and-you're-out, not any glares or harsh words. There was just the two of them. Penny and Sheldon – there. At this moment in time: together.

And as he gently lay her across her bed, hovering over her and raining tender kisses all over her face, he for once believed something he'd previously believed as hokum.

Because at this moment in time he decided that, yes; he and Penny did belong together.

~ Fin ~

A/N: Sweet, huh? :) Aww, it almost broke my heart to write about him crying. I'd never pictured Sheldon having THAT amount of emotional pressure before, but for this it felt... well, right. Even if I do say so myself.

Look out for more Sheldon/Penny fan-fics from me. :D I have a feeling this couple is going to stick with me for a long time! Also, Howard/Raj. They're one of my favourite couples, too!

I hope you enjoyed my story, reviewers get to... well, you read it. ;) Teehee.

Kelly xxx