Sheldon peered in shock at the figure of the beautiful blonde unpacking boxes in the apartment across the hall. It was Penny, all right. She had grown her hair longer and dyed it an improbable shade of platinum, but she would always be beautiful to him no matter how she changed her appearance. He was so stunned to see her that he could do little more than parrot Leonard's platitudes like an idiot.

Back inside the safety of their apartment, Leonard started talking about inviting her over for lunch. Sheldon did his best to dissuade him, but he was still overwhelmed at seeing Penny again after all these years. She had been his first and only love, the one woman who had ever distracted him from his single-minded pursuit of the Nobel prize. Then she had betrayed him, and he vowed he would never let anyone else get close enough to break his heart again. Now his mind was racing in circles, wondering how she could be back in his life. He didn't know why she was acting like she didn't know him. Clearly, her moving in across the hall from him couldn't be a coincidence. As if sensing Sheldon's uncertainty, Leonard kept pressuring him until he reluctantly gave in and agreed to invite her over.

Almost from the moment she stepped into the apartment he shared with Leonard, Penny was immediately drawn to his work. She never had understood his research. Although Sheldon was a bonafide genius, he was woefully inadequate at explaining his ideas to others. Still, he couldn't help the smile that spread across his face when she called him a "beautiful mind". John Nash was a genius of the highest caliber, and it appealed to Sheldon's ego to be compared to him, even if he wasn't sure how much Penny had actually taken away from that movie. He remembered, as if it were yesterday, how they had watched it curled up in bed together in their tiny apartment. As always in those days, his attention had been divided between his love of science and the alluring woman next to him.

Her admiring smile quickly faded to a look of confusion and pity when he panicked to see her sit in his spot. His neuroses (quirks, she used to call them) had gotten much worse in the past few years. Strictly regimenting every aspect of his life was one of the ways he now used to protect himself. That fact that she unerringly made her way to the one place that was the center of his existence unnerved him. He was determined never to be hurt again, which meant he had to discover what she was doing here. He'd turned his back and walked away from her three years ago. Now she had reappeared in his life, and he couldn't help but ascribe nefarious reasons to her unexpected return. When she suddenly began crying, saying her boyfriend had cheated on her, he thought he understood. Money had always slipped through her fingers. Apparently, she hoped to throw herself on the sympathies of the man she had once claimed to love.

Later, when she came back asking to use their shower, his anger started to burn at her flippant disregard for his privacy and her obvious attempts to distract him. This was how she operated, he thought, using sex to manipulate. Leonard was already developing a crush on her and stared after her longingly. Much to Sheldon's chagrin, all his resentment couldn't completely dispel the arousal he felt. There were many images, seared into his mind, of water cascading down her perfect form, of the two of them gliding soap-slicked hands over each other's bodies. With a groan, he gave up and headed to his room for some privacy. Earlier that day, he had allowed Leonard to think he might make use of the magazines provided at the sperm bank, but the pictures in them wouldn't have affected him at all, except to disgust him. Penny was the only one who had ever filled him with desire, the only one he had ever wanted. For him, there would never be anyone else. At one time, he thought his constancy was a positive trait, but it had only served to haunt him after he found out she'd been unfaithful.

Four years ago:

Sheldon gazed around his one-bedroom apartment. All of his belongings were unpacked. His reproduction bat'leth hung on the wall in his bedroom, his bookshelves were filled with an assortment of textbooks and superhero memorabilia, and his Batman cookie jar was carefully centered on the kitchen counter. His living room contained nothing more than a couple of lawn chairs and a TV, but that was because he didn't plan on having any visitors. If he ever had any, he imagined the uncomfortable chairs would discourage them from overstaying their welcome. He was pleased with his choice of a new apartment. Although he had to do all of his research for housing online before moving from Germany, he felt he'd naturally made the best choice. As he possessed an IQ of 187, it would have been difficult for him to do other than succeed. He was within easy walking distance of the grocery store, a comic book shop, and Caltech, where he would be working toward his second doctorate in theoretical physics. The only thing that remained was for him to find restaurants which met his stringent requirements. Once he had his weekly meal schedule set up, he would be perfectly comfortable and completely solitary, just the way he liked it.

Three days later, he found himself once again at the mercies of an unknown culinary staff. The waitress had been friendly enough. Actually, she'd been too friendly, and the way she smiled at him aroused his suspicions. No one smiled at him on purpose, at least, not once they understood what he was like. This was especially true when it came to women who were as aesthetically pleasing as she was. So he proceeded to order his dinner: a bacon, barbecue cheeseburger with all the toppings on the side. Her smile slipped a little as she informed him that the cheese wouldn't be melted if he ordered it that way. So he enlightened her about the utter chaos that would ensue if the condiments were placed on his burger in the wrong way and how he didn't trust the knuckle-dragging troglodytes in the kitchen to get his order right. Then she did the strangest thing: she laughed as if he'd said something funny.

"Sweetie, I think you just made my night. What did you call them again? Tractor dykes?"

With a sigh, he explained that the term "troglodyte" was a term which originally meant a cave-dweller, but had come to mean a primitive, ignorant person.

"I guess you learn something new every day," she replied in a cheerful tone.

The aphorism wasn't true for him, but that was the burden of being a genius with an eidetic memory. In a way, he appreciated her attitude. Most people he met hated it when he corrected them, but this waitress was so far beneath him in intelligence that she was almost like a blank slate. He wondered what might happen if he took a person such as her under his wing and educated them, expanding their mind to its fullest potential. The idea was amusing for approximately one point five seconds. Then he quickly shook his head. He wasn't usually so whimsical. He blamed it on the disruption to his routine.

When the waitress came back, he was pleasantly surprised to see that she had gotten his order exactly right. He craned his neck a little to see the name tag that was hidden from view by the curves of her bosom. "Thank you, Penny," he said.

She stared at him for a second with an odd expression before smiling again and telling him to enjoy his meal. He wondered what had been behind that look she'd given him. That was one of his biggest failings, one that he hated to admit: he struggled to interpret facial expressions and tone of voice. In general, he knew that a smile was a good thing, and a frown or yelling were bad things. But there were so many nuances of emotion that went completely over his head. Plus, people had the baffling tendency to say things they didn't mean, or smile when they were actually displeased. He'd long since given up trying to make sense of social context. That was why he loved working with theoretical concepts; they could be proven or disproven with mathematical principles. Unlike emotions, his work was completely objective.

It didn't take much deliberation on his part to make the Cheesecake Factory his Tuesday night restaurant. He tried not to think about why he had placed it on a Tuesday. Mondays made him happy because that was the first day of his doctoral-level classes; Wednesday was new comic book night; Thursday was model train night; Friday was vintage video gaming night, and on Tuesdays, he saw Penny. He quickly noticed that she wasn't a very good server. She often ignored her other tables, even when the occupants were trying to flag her down, as she stood and chatted with him. Ordinarily, he wouldn't have appreciated her attempts to engage him in conversation. But there was something about her, a kindness which reminded him a little of his mother. A few weeks later, she altered their routine. When she handed him his receipt, there was a ten-digit number written across the bottom. "What's this?" he asked her, slightly puzzled.

She rolled her eyes. "It's my phone number, in case you want to call me sometime."

"Why would I do that?" he asked.

The smile quickly disappeared from her face. "No reason, I guess," she muttered. She snatched back the bill and quickly crossed out her number.

He frowned at her, puzzled. "Were you attempting to engage me in an alternate social construct?"

She shrugged. "I have no idea what that means. It's just that you always come in here by yourself, so I thought you might like someone to talk to. We could hang out sometime."

He peered at her curiously. There were many responses which ran through his mind. After all, he was a theoretical physicist, and she was a waitress. He wasn't sure they could find a mutually agreeable subject to discuss. But unless he was mistaken, the offer of her phone number was a foray into a paradigm alteration. "You want to spend more time interacting with me?" he asked slowly.

A flush crept across her face. "Yeah, I mean, I like talking to you. You always come up with these crazy smart ideas. You're not like any other guy I've met, and I think you're kind of cute, so…" She shrugged again. It was another of those social conventions which left Sheldon feeling as if he were trying to solve an equation with only half the data. He wasn't sure what she wanted, but his tiny apartment was sometimes too quiet. He told himself that a simple conversation with a simple person might help him order his thoughts. Sometimes, when he was wrestling with a difficult problem, his mind tended to race around in circles until he got stuck. He nodded and recited her phone number.

"Oh, wow, can you still read that?" she asked, gesturing toward the receipt.

He shook his head. "I have an eidetic memory. I remember everything… at least, everything I consider worth my attention."

The color in her cheeks deepened, and she smiled at him again. "Oh, okay. So give me a call sometime."

A/N: I'm posting this to tie up loose ends & try to do something with my half-finished stories. I'll be honest with you, this was one of the shorter ones. Any Shenny fans still out there, give me a shout-out! And the haters? Well, they serve their purpose by upping the read/review count. :D Enjoy!