Big Bang Theory 1. Chapter 1

Chapter 1

_Knock. Knock Knock._ "Penny."

_Knock. Knock Knock._ "Penny."

_Knock. Knock Knock._ "Penny."

Penny stood from the sofa and headed to the door, wobbling slightly as she walked. She'd had quite a few glasses of wine. She opened the door to an annoyed looking Sheldon- who else would it have been?.

"Can I come in? Leonard has a woman in his room and they're being rather loud." He pursed his lips in disapproval and Penny giggled. He was so rigid when it came to sex.

"Sure thing, Shelly." Her words were slightly slurred but he didn't comment on that. He just stepped inside her apartment and perched himself awkwardly on the edge of her sofa. She joined him, pouring herself an extra glass of wine as she sat.

"Want a glass?" She teased. She had always found teasing Sheldon very amusing.

His lips pursed even tighter. "No, thank you."

She giggled again. Wine always made her giggly, it was why it was her preferred drink. She studied Sheldon as he sat formally on the seat, peering around her apartment as if he hadn't been in here a hundred times before. She could tell he had something on his mind.

"Penny," he finally asked. "Why is everyone so obsessed with sexual intercourse? People lose their morals and break promises for this one carnal act. I don't understand."

Penny rolled her eyes at him. "Of course you don't understand, you've never experienced it."

Sheldon scoffed at her. "That is no argument. I'm a theoretical physicist- I don't experience ninety-nine per cent of what I understand."

She nodded, accepting his point but pushed ahead anyway. She wanted him to understand. "Yes. But there are certain things that you can only understand by experiencing. Sex isn't purely physical, it is emotional as well. The excitement, the intensity, the adrenaline… There are not many experiences in life that give such a concentration of emotions."

Penny sighed, annoyed at herself. She wasn't explaining it right. Sex wasn't something that could be explained- which was just what she was trying to explain to Sheldon. She would have to try a different approach to the subject.

"Have you never been curious about this area of science before, Sheldon? I would have thought that you would have made an effort to learn about everything you could."

Sheldon stiffened in offence at her words. "I hardly think that this is the most important subject I could be spending my time thinking about, Penny."

Penny sighed in frustration. "It should be. This is something that links every human- the need to mate. It's powerful and instinctual and it doesn't require a genius to understand it. Maybe you think you're above this knowledge but as a scientist you should be ashamed of yourself for not understanding something so basic."

She watched him think over her words. He looked as if he wanted to deny what she had said but she had learned that if you stated something rationally to him he wasn't able to refuse it. Sheldon's brain loved rationality the way she loved shoes.

"So what you're saying is that I should experience sexual intercourse if I want to understand why people act the way they do?" He stated slowly. "That's preposterous. I have never wanted to experience something so unhygienic and I have never wanted to be that close to someone."

Penny chuckled. She should have known that she couldn't persuade Sheldon to do something that required skin to skin contact with a human being. He was afraid of his personal space being invaded and he was even more afraid of germs. He was a lost cause if ever she had known one.

"You've been kissed before though. That's unhygienic and requires being close to someone." Penny pointed out in a teasing tone.

"I would hardly say I'm an expert in that field, Penny. I've never even- what's the expression- French kissed someone." Penny replied sardonically and Penny felt a jolt of surprise. The poor man had never even been thoroughly kissed? No wonder he had no understanding of anything of a sexual nature. Penny had frenched more guys than she could remember.

"Really? Not even Amy?" Penny asked, trying to keep the amazement out of her voice. She knew that when Sheldon and Amy's 'Relationship Agreement' had ended they had decided not to renew it but she had assumed that they had kissed properly at least once.

"Good Lord no. She tried to, but I never wanted to. I liked Amy but not in that way." Sheldon admitted aghast.

Penny contemplated kissing him. She was drunk enough to think that she could convince him to kiss her when no other woman had before. She was drunk enough to think that she could open the door to sexuality for him. She wouldn't sleep with him of course- he was her ex's roommate. But one kiss wouldn't mean anything, would it? She leaned towards him when he stood up impatiently and she almost fell flat on her face.

"Do you think they will be done yet? I want to go to bed." Sheldon asked, an air of annoyance surrounding him.

Penny muttered a muffled "probably not" against the cushion but Sheldon ignored her and strode to the door.

"Thank you for your company tonight, Penny. No doubt I'll be back if Leonard is still preoccupied." He opened her door and strode out, shutting it behind him.

Penny stared in wonder at the closed door. Had she honestly just considered kissing Sheldon Cooper? More to the point, had she, for what must be the first time in her life, just been turned down?

"Too much wine," she decided definitely, dragging her sorry ass to bed.


	2. Chapter 2

Chapter 2: His first Assignment

_Beep! Beep!_

Sheldon jolted to awareness as his message tone roused him from his almost sleeping state. Who on earth was texting him this late at night? With a muttered grumble, he turned onto his side and picked his phone off the bedside table.

The brightness of the screen made him squint his eyes as he clicked onto messages. The message was from Penny- what on earth did she want? He had only left her house an hour ago. With a small shake of his head he opened the image and blinked in surprise. A pair of woman's breasts immediately filled his vision and for a moment he couldn't look away. Then he noticed the words at the bottom of the screen and he quickly focussed on them.

'_Call me teacher cos I'm gonna teach you everything I know about sex. Next time you DIY look at these- don't worry their not mine!'_

First Sheldon pursed his lips. Would Penny never understand the difference between 'their' and 'they're'? Then he reread the message and realised that he had no idea what Penny was trying to convey. DIY? Why would Penny think a pair of breasts would help him build a bookcase or something similar? Evidently Penny was referring to a context that Sheldon was not familiar with and he surmised she meant something related to coitus due to the contents of her message. With a shrug, he put his phone down and rolled back over onto his back. Within moments he was asleep.

The next morning, as he sat in his spot on the sofa with a bowl of cereal and watched Leonard's coital partner leave, Sheldon again tried to decipher Penny's text. Ordinarily DIY was an acronym of Do It Yourself- did Penny mean the same or did the letters stand for something else? If they stood for something else then what did they stand for? It was so aggravating being out of the loop.

As Leonard shut the door and sat on the chair with a smug grin on his face, Sheldon realised that Leonard may have an idea what Penny had meant- after all Leonard had dated her in the past, surely he must be used to her colloquialism.

"Leonard, I received a confusing text from Penny last night and I need you to help me decipher it." Sheldon stated, interrupting Leonard's post-coital glow and over the top grin.

With an annoyed sigh, Leonard turned towards him. "Okay Sheldon, what did she say?"

"She sent me a picture of breasts and told me to look at them when I DIY."

Leonard gaped, opening and closing his mouth like fish.

"She sent you a picture of her breasts?" Leonard shouted.

"Good Lord Leonard, keep your voice down." Sheldon chided. "The picture wasn't of _her_ breasts.Now please will you tell me what she meant?"

Sheldon watched Leonard's brow furrow in confusion. Was Leonard as clueless as he was? Was he going to have to ask Penny what she had meant and admit the extent of his ignorance? That would be humiliating to say the least.

After a moment, Leonard sighed. "Ok Sheldon, she meant next time you masturbate. Do It Yourself… do you see what I'm saying?"

Now it was Sheldon's turn to gape in amazement. Penny wanted him to masturbate to an image of a woman's breasts? Aside from his mother's, the only breasts he had seen were, in fact, Penny's from when she dislocated her shoulder- yes, he'd peaked. And then he'd only seen a glimpse. But now he had a picture on his phone that he could look at whenever he wanted, not that he would want to. Penny was crazy is she thought he would actually complete her 'assignment'.

He finished his cereal in silent contemplation before putting the message out of his mind and continuing his day as normal.

The next morning Sheldon woke with an erection. This wasn't at all uncommon but for the first time he wondered if he should follow through with Penny's orders and picture something while masturbating. Telling himself that the thought was errant and he was crazy for even entertaining it, he began to relieve himself quickly and efficiently, his mind elsewhere. But the thought kept pestering him: should he try it?

Sighing in irritation at himself, Sheldon reached for his phone with his spare hand and opened the image. A scientist should try everything once, he thought to himself. He stared at the image to memorise it (even though it really only took him three seconds or so to do so) before returning to business.

He pictured the breasts as he resumed stroking himself up and down, up and down. He pictured the puckered pink nipples and round fleshy mounds around them and found it made little difference to his routine. Was he doing this right? He felt no different, nothing but the barest stirrings of lust which he was used to beating down.

Instead he used his exceptionally graphic mind to picture his hands on those breasts. He wondered how those nipples would feel. Obviously they wouldn't feel the same as rest of the breast. He thought back to when he had glimpsed Penny's breast and remembered how soft her skin had felt under his hands as he helped her dress.

Yes, the softness he felt then he imagined his hand stroking over, cupping maybe, possibly squeezing. Yes, he felt his lust stirring higher, still controllable, still minute, but there nonetheless. He imagined rubbing a thumb over the nipples, they would be harder, like Goosebumps he imagined. His excitement picked up a little more.

He closed his eyes as he imagined it, increasing the pressure and speed of his right hand. He imagined the heat the skin would radiate, heat that matched what he could feel in his hardened shaft. With a soft groan, he felt his release spread through him, more intense and more powerful than ever before.

Contemplating, he cleaned himself up. Perhaps Penny had been right, he had certainly felt different there- not much so, but different all the same. He almost wished that his relationship with Amy Farrah Fowler was still on-going so he could compare the results to seeing her breasts and then masturbating over that memory. Would it be more intense if it was someone he knew? Or less so? He had never before desired to see any more of a woman's body, not even Amy's. Maybe Penny was teaching him something after all.

**A/N: So we use the expression DIY a lot where I'm from but I'm sorry if you don't. I honestly have no idea what slang from other places about these topics is like so bear with me ****. Thanks for reading and sorry about how long it took to update- I'll try to be much faster in the future!**


	3. Chapter 3

**A/N: sorry it's been a while since updating but I've been very busy with uni and work. Thanks to everyone who reviewed- you know who you are.**

Chapter 3: His first kiss

A week had passed since Penny had set Sheldon his first task. In that time she had been over for dinner four times but she had not asked whether he had completed the task or set him a new one. His curiosity was piqued now though, and he wanted to know what task she would set next. But he wouldn't bring it up, wouldn't let Penny know how much this 'experiment' had affected him.

He glanced over at her. She was seated on the floor by the coffee table with a carton of noodles in front of her. Instead of eating, she was texting on her phone, her fingers flying fast over the keys. He watched her until she placed the phone on the table and resumed eating her noodles with a small smile on her face.

His phone loudly announced a text message and he jumped in surprise. As he took his phone from his pocket, he noticed Penny's bright gaze was on him. His cheeks flushed in a slight blush.

_Meet me at my house at 8 cos teacher has a new lesson planned_

Sheldon's eyes caught Penny's again. It was only just after six now, he'd have almost two hours of suspense before her next lesson. He knew Penny had deliberately left him in the dark- she knew very well it would drive him crazy. She winked at him- proving his point- and he nodded once in return.

The rest of dinner passed in excruciating slowness; it seemed he checked the clock every five minutes. Finally, _finally, _the others in the room cleared up and headed out to the cinema. They had invited Sheldon and Penny but he had passed due to the cinema's lack of red vines and Penny had scoffed at the 'geeky-movie choice'. Penny had also left, leaving him alone for thirty minutes with his overactive mind.

He paced the floor until it was time to go to Penny's. As he crossed the hall he noticed his palms had begun to lightly sweat in nervousness. He wiped them on his trousers.

_Knock Knock Knock_

"Penny."

_Knock Knock Knock_

"Penny."

_Knock Knock Knock_

"Penny."

The door opened to reveal Penny standing with her hand on her hip and a smile on her face. She wore very short denim shorts and a bright pink camisole top and her hair cascaded wildly over her shoulders in waves. Sheldon felt stirrings of lust and struggled to subdue it. He assured himself that it was only because he had pictured her breasts in his last task and resolved never to do so again. He closed his eyes briefly to banish the image in his mind of her perky breasts.

"Come on in, Sheldon." Penny chirped energetically.

He entered her apartment and stood awkwardly in the centre of the room, unsure of what to do next. He was surprisingly pleased to note that she had actually tidied the place up- it was far from its usual state of disarray. Penny shut the door and turned to face him.

"So have you completed the first task I set you?"

Face and ears redder than they had ever been before, and more embarrassed than he could ever remember being, Sheldon coughed out an affirmative. A large grin lit Penny's face and she chuckled lightly.

"And did you enjoy it?"

Again he answered positively and again she smiled triumphantly.

"Today's task is to French kiss someone. To French kiss me, Sheldon." Penny's voice seemed to purr seductively at him, yet he couldn't get the thought of bacteria out of his mind. She must have seen the face he pulled thinking about the germs. "Don't worry- I'm going to do my best to make this as clean as possible for you."

Before Sheldon could puzzle out her meaning, Penny sauntered through the door that led to her bedroom. He followed her hesitantly and saw she had gone into the bathroom. When he entered behind her, he blinked in surprise at what he saw.

On the cabinet Penny had placed two toothbrushes, still wrapped in plastic, toothpaste, dental floss and mouthwash all in a neat row. She raised her eyebrow at him as she removed a toothbrush from the plastic and began to clean her teeth. Sheldon followed her example with the other toothbrush, pleased to note she did a thorough job. They brushed, flossed and rinsed in sync before heading back into the sitting room and sitting on the sofa.

"Is this okay? I mean, I figured that if we brushed first, you would be more comfortable." Penny asked, the first hint of hesitation creeping into her tone.

He nodded in affirmative, well aware that he had never been this quiet in all his life. He couldn't tell her that he was touched by her actions, that they made her seem so precious in his estimation. Not even Amy, who he had thought to be like him, had thought about germs before kissing him. Maybe that was why he hadn't enjoyed Amy's kisses. Would this one affect him then, this kiss with Penny? Already she was affecting him more than he was comfortable with.

Facing each other on the sofa, Penny leant towards Sheldon until her lips were a mere inch from his own. He licked them nervously before closing the rest of the distance.

Her lips were soft- softer than he'd imagined they could be. They pressed against his gently, sweetly. Stunned, he gladly let her take control of the kiss. She gently prised his lips open with her own and began to move them against his.

His lips felt on fire with passion. He longed to reach his hands up but he didn't know where to place them. On her arms? In her hair? There were too many choices so he fisted his hands and kept them by his sides. Just when he thought he was learning the rhythm and the motion of the kiss, Penny changed the dynamic. Her tongue darted into his mouth and lightly stroked his own. He almost moaned at the contact, it was so heady, so perfect. Tentatively, he mimicked her motions with his own tongue, stroking it along hers and exploring her mouth. He thought he heard her intake a breath of surprise but was too caught up in the moment to consider anything other than the kiss.

Too soon, Penny pulled back and gasped for breath. Sheldon did the same- slightly dizzy from the lack of oxygen in his lungs. He gazed at Penny was glazed eyes. She alone had shown him attraction and lust as he had never felt it before. Why her? Why was she- a woman who was, on paper, unremarkable- considered by him to be an extraordinary woman and capable of rousing these feelings within him? He didn't know. He only knew that he wanted to know what other lessons she had to teach him.


	4. Chapter 4

**A/N: Thank you to everyone who reviewed! It's very much appreciated.**

Chapter 4: Latex Gloves

Penny entered Sheldon and Leonard's apartment knowing that Leonard was out on a date. She wanted to catch Sheldon alone- to invite him over for another lesson this evening. Thought to be honest, she had considered abandoning their lessons when she had realised how caught up she had been in their kiss the other day. For a moment she hadn't cared that he was a socially awkward, ridiculously nerdy genius who also happened to be the roommate of her ex-boyfriend.

But after he had left her apartment, with a dazed expression fixed on his face, it had all come rushing back to her. She shouldn't have kissed him; she shouldn't have wanted to kiss him. Even though she hand Leonard had broken up, twice now, she knew he still cared about her and that if anything happened between her and Sheldon he would be devastated. Hell, if he found out she had kissed Sheldon he would be heart broken.

But she hadn't been able to stay away for long- barely two days, in fact, had passed since their kiss.

She closed the door silently behind her and looked around the apartment. Sheldon was standing in the kitchen, his back to her, unaware of her presence. Perfect. Making an effort to keep her footsteps mute, Penny padded across the floor until she stood behind Sheldon.

"Boo!" She whispered.

Sheldon jumped and spun around to face her. Penny couldn't help it- she laughed loudly at his reaction.

"Good Lord, Penny. You scared the bejesus out of me." Sheldon scolded her.

"Sorry." Penny looked over Sheldon. He was wearing black pants and a red flash t-shirt over a white one. He looked the same as he did everyday but today she found the combination… cuter than usual. "Come over to mine tonight? We've got to continue your education."

His eyes flashed in excitement. "And what will you be teaching me today?"

Penny felt her lips curling into a grin. A couple of weeks ago Sheldon's reaction to the prospect of anything carnal would have been disgust or, at the least, disinterest but it certainly wouldn't have been excitement. And the best thing was that he only reacted to her in this way; she was the only one to interest him sexually. So stay away from him? No, she couldn't.

"Something I'm sure you'll enjoy. Come over in an hour." Without waiting for a reply, Penny sauntered out of the room, making sure to sway her hips seductively, and headed back to her, for once tidy, apartment.

She was becoming a nervous tidier. Every time she thought about Sheldon's lessons she would worry that he wouldn't enjoy them and she would clean her apartment until she was too tired to think about it. It was weird, having washed clothes and a clear floor, but she couldn't deny that she liked it. This time while she was waiting for Sheldon, she ran the vacuum cleaner over the floor and dusted the coffee table.

Of course, he arrived precisely an hour after she had left his apartment and rapped on the door with his custom knock that he never deviated from.

_Knock Knock Knock_

"Penny."

_Knock Knock Knock_

"Penny."

_Knock Knock Knock_

"Penny."

She opened the door for him and stood aside as he entered. He looked around, as if for some clue to his lesson, before sitting gingerly on the edge of the sofa. She padded over to him and sat down beside him.

Penny put her hands into her pockets and pulled out a pair of latex gloves, a grin lighting her face and confusion shadowing his. "Sheldon, take your shirts off."

His eyes widened in disbelief and a deep red blush covered his cheeks. "Excuse me, Penny?"

Penny pouted at his resistance. "Come on Sheldon, please. Look, I've got latex gloves so I can't infect you with germs."

Sheldon shook his head violently though he never moved from his spot on the sofa. "No. Definitely not. I'm sorry Penny, but I can't."

Though disappointment coursed through her, Penny forced herself not to push the issue. She would have to take baby steps with Sheldon, she reminded herself. Instead she sat on his lap, causing his eyes to saucepan in reaction. She lowered her voice into a purr. "Okay then, keep them on, I don't mind."

She snapped the gloves onto her hands and placed them on his shoulders over the t-shirts. The she lowered her lips to his in a brief kiss. To her relief, he didn't complain that they hadn't followed the same rigorous teeth cleaning process as last time. Of course, she had brushed her teeth before his arrival and she could taste the mint on his breath that indicated he had done the same. Her tongue brushed against his in a rhythm that already seemed familiar, a light teasing touch. Penny let out a small moan and deepened the contact.

When she was sure Sheldon was distracted by the kiss, she slid her hands to his stomach and slipped them under the shirts. Even through the gloves she could feel the heat radiating from him and the surprising firmness of his skinny frame. She pulled back from the kiss as her hands ran teasing patterns over his stomach.

"You like?"

He nodded in affirmative even as his eyes darkened with lust. Satisfaction filled Penny with the knowledge that he was enjoying her touch. She didn't want to stop touching him. So she didn't- she slid her hands higher up instead, circling a nipple with the pad of a finger and delighted when she felt his cock stir and harden beneath her.

Holy shit! She was having this effect on Sheldon? She felt her own desire rising in reaction to his and gently tugged at his lip with her teeth in the universal sign for 'give me more'.

She wasn't disappointed. Though this was Sheldon's first make out session, his instinct guided him to pull away from her and gaze at her face with his now almost black eyes and demand what he wanted.

"I want to touch you too."


End file.
