Later that night when she got home from work she got changed into her usual pink shorts and blue tank top and went next door to join the guys for Thai food.

"Penny here is yours." Leonard said the second she entered their apartment. She threw herself into the arm chair and tucked into her food, idly listening while they argued over some theory Leonard was working on. She noticed that Sheldon and Howard were sat next to each other and she was very glad to see that they had made up, despite the fact that they were arguing now. The fight got so heated in fact, well as heated as nerds could get, that Raj after twitching awkwardly since the fight began threw down his chopsticks and shouted "Shut up!" causing everyone to stop and stare at him in amazement.

"Well said sweetie!" she said cheerfully saluting him, he smiled proudly at her before turning back to his food then he realised he had nothing to eat with. She sighed and slipped him a clean set of chopsticks.

"OK now that you guys have shut up can I ask you something?" Penny asked.

They all muttered agreeably so she carried on. "When are you guys gonna cut your hair? You guys look like a big foot family reunion." She couldn't help but snicker at her own joke.

"Yeah we know, but we haven't had time to book an appointment yet." Leonard said dejectedly.

"Well hey why don't I cut your hair for you?" she said.

"You have training I assume?" Sheldon said with one eyebrow raised.

The other three looked at her as if to say just say yes for the love of god!

"Yes of course!" she lied smoothly "I cut peoples hair all the time!" that part was actually true.

"Well then I guess you may proceed." He said reluctantly and went off to find the hair scissors and a towel.

"OK who's first!" she said happily when he returned. Leonard hopped up and went to wet his hair, she shook her head sadly; it seemed he still had a crush on her which always made her feel guilty that she can't return his feelings. He sat on the floor with his back leaning against her legs and she placed the towel around his neck to catch the stray hairs. Once she was done she sent him to the bathroom to shave and Howard took his place, then Raj when she was done. By the time she had finished Raj everyone was bored, and they decided to go to the comic book store which put Sheldon in a foul mood as he stormed off to wet his hair. She glared as they dashed out the apartment before he got back.

"At least buy him something while you're there!" she called after them as the door swung shut. Eventually he came out of the bathroom and sat back in his spot.

"Erm Sheldon you have to sit on the floor so I can reach your hair."

"I am not sitting on the floor. This is my spot Penny."

She groaned and knelt on the sofa. "Scoot forward" she said and he did so she slipped behind him and sat on the back of the sofa with his back between her legs. He seemed a little reluctant but surprisingly he didn't put up much of a fight, it seems it he was comfortable as long as he was in his spot. She couldn't help but blush as he settled between her legs, even though the situation was not remotely sexual. She placed the towel around his neck and combed out his thick dark hair.

"So what type of cut do you want? What you had before or do you want something different? I mean you have a lot of hair now there's a lot to work with."

"My usual cut, but a little longer than before please."

"Okay you got it honey"

Twenty minutes later she had finally finished his hair and was cleaning the stray hairs from his neck.

"OK all done!" she pronounced proudly. His hair was now a lot shorter but long enough to run your fingers through, she had even given him some bangs that showed off his blue eyes, and she was glad to see that he still looked the same. She handed him the mirror nervously so he could see what she had done. There was a very pregnant silence while he examined his new hair cut. She slid from the back of the sofa until she was next to him and watched him, biting her lip in anticipation.

"I must say Penny," he began "I hated it when I first saw what you had done to my hair since it was different from my usual style. However after more deliberation I have decided that this cut in fact suits me very well. Thank you Penny."

She beamed. "Thank you Sheldon. Now you can go out and pick up all those cute physics girls." She said, using the towel to get rid of the itchy hairs that were still clinging determinedly to his pale neck.

"Penny I don't see what my upper body strength has to do with women." He said

She held in a giggle. "No! Pick up as in... attract!"

He blinked at her.

"You know to get a girlfriend?" she said helplessly

"Oh I have no need for a girlfriend. In fact I have no doubt that having one would hinder my present endeavours."

"What? That's crazy! There are lots of good reasons to have a girlfriend. Are you saying you haven't had fun with your previous girlfriends?"

"Well my experience with Ramona was, while very helpful to my career, highly uncomfortable and put a huge strain on my daily routine."

"Yeah okay Ramona is a totally bad example. But there have been others right?"

He looked away from her, his face contorting into his usual "stressed" expression.

"Ramona has been your only girlfriend?" she asked in wonder "But how can that be? You're a great guy! You have a cool job, you're good looking, and you're totally smart. Why haven't you had more girlfriends?"

"As I have said before I neither want nor need a girlfriend."

"Wait, hold on a second. Does this mean you haven't kissed anyone before?"

He blushed.

"Sheldon! That's insane!"

"I don't see why."

"Well...it just is!" she thought for a moment, deciding whether or not to suggest it. "Hey I have an idea. Why don't we kiss? You can see it as one of your social experiments?" she felt so embarrassed for suggesting it, but she couldn't let the poor guy carry on never having been kissed, and who knows, maybe it will spark his interest in relationships.

"I don't see how that will benefit me in any way."

"Sure it will! It will be another experience to put under your belt!" she winced slightly at her choice of words.

"Penny, I am not denying that you are in fact a very beautiful woman, and I am flattered that you would offer to do this. However I am going to refuse on the basis that it will upset Leonard and that will in turn make him intolerable to live with."

"Oh" she thought about that for a moment "Well we don't have to tell him." She wasn't sure why she was pushing this so hard, and if she was honest she didn't want to delve into that in more detail as she was afraid of what she might discover.

"Penny you know full well that I am incapable of keeping a secret."

"Fine" she said and before he could do anything she leaned forward and pressed her lips to his. To say he was startled was an enormous understatement as he leapt about a foot into the air. He pulled back and stared at her in horror and she immediately regretted it.

"There it's happened, now relax and enjoy the experiment." She said playfully wiggling her eyebrows, hoping the entire time that he won't completely reject her and embarrass her.

He sighed in exasperation. "Fine! Since it has already happened and you are my friend I don't see why we shouldn't explore the experiment."

"Aw I'm your friend?" she said flushing with pleasure.

"Of course you are Penny," he said baffled "why else would I have tolerated you for three years?"

"Of course." She said her smile fading slightly. "You ready?"

"Ready? Well I suppose in this instance one can assume the I am, however—"

"Sweetie? Not the time." She said shaking her head and he clamped his jaw shut. "Now close your eyes."

He obediently closed his eyes, though she could see his hands were clenched into tight fists. Penny knew that she needed to do it quickly before either of them lost their nerve, so she leaned forward and caught his lips with hers again, raising her hand to his cheek to try to calm him down as he froze beneath her lips. She pulled away slightly to reposition her lips, and as their lips met again she could feel some of the tension leave Sheldon and he relaxed into the kiss. She felt a bit braver and so she began to slowly move her lips against his and felt a surge of triumph as he gently placed his hands on her waist and clumsily began to return the kiss. She moved the hand that was on his cheek until her fingers laced through his hair and his fingers dug a little tighter into her waist. Taking this as encouragement she slowly ran her tongue over his lower lip, asking for entrance and was surprised as his lips parted immediately and their tongues touched. In that instant the kiss changed from shy and curious, to clumsy and erotic. She forgot that this was merely a social experiment and threw herself completely into the kiss. Her arms locking around his neck and he instinctively pulled her closer, his arms slipping around her holding her against him, their tongues moving together sensually causing her to moan slightly. She pulled away after a couple more seconds and they were both breathing as though they had run a marathon instead of a 40 second kiss. They stared at each other uncertainly; their arms still wrapped around each other, until she gently untangled her arms from his hair and scooted backwards down the sofa, never looking away from his gaze as she was unsure as how he would react. He sat there frozen, his arms hovering as though they were still wrapped around her, the memory of which made her blush.

"Sheldon sweetie?" she said nervously "Are you ok? Should I go?"

He twitched as if he only just registered she was still there and nodded stiffly before walking out the room, his hand over his mouth. She sat there until she heard his bedroom door close. She got to her feet unsteadily and left the apartment. She entered her own apartment and sank onto her sofa, tears spilling down her cheeks. What had she done?