He was an animal. There was no two ways around it, once thoughts of germs were shoved to the back of his head, once he allowed himself to touch her, really touch her, and not have to worry about propriety or the others finding out that he harboured feelings for her, about the teasing he was sure would have resulted, he set about proving that not only was she not too much for him, but that he could handle anything she dished out.

And there was nothing Penny liked more than a little friendly competition.

She and Sheldon had always been that way, when one pushed, the other pushed back harder, testing limits, seeing how far the other would go before conceding defeat... And tonight, neither of them were willing to settle for anything less than full out war.

Sheldon had logic on his side, his knowledge of physics, the ability to remember every word he'd read in every book about sex that he had searched out both when he was fifteen and when Penny had showed up at his apartment building, boxes in hand, all little denim shorts and long blonde hair and a smile that made the world alright, a set of ethics that matched his own.

Her fighting spirit was one of the best things about her as far as he was concerned.

She challenged him, and it made him feel. Really feel.

Penny had a different kind of knowledge, and a wealth of experience on her side. She knew what she liked, she knew what men liked, and she knew Sheldon, better than anyone except his family.

When he informed her that she wasn't going to win, because he'd been reading extensively on the subject at age 15, she snorted and licked at trail up the side of his neck, nibbling on his ear as she told him that she'd been reading hardcore romance novels since the age of eleven, and dry science publications had nothing on heart stopping, stomach dropping, smut.

It was then she discovered that proper Sheldon liked it very much when she talked dirty. He liked it even more when she called him Doctor.

She was considering early victory when he showed her what else his physics scrawling, piano playing fingers could do...

He noticed everything, and he'd always found her fascination with watching his hands interesting, now he felt a glimmer of triumph when her eyes rolled up in her head and she moved against him.

Again and again that night, they declared a tie, until she introduced him to the shower and got down on her knees. His back against the tile, he declared momentary defeat, he would have declared anything, just so she didn't STOP.

He made sure to get her back later.

The next few day went by in a blur, meetings, conferences, lectures, all prim and proper in public except for glance here and a touch there, and then once the door was shut, it was ON.

He had a lot of lost time to make up for.

She was determined to keep up.

They both knew once they got home, it would not be so easy. Work, life, Leonard, all would interfere, but instinctively they both knew they could make it work. They would not allow it not to.

The drive home was quiet, Sheldon slept most of the way. When they pulled into the parking lot of their apartment building, they immediately noticed the increase of cars, the Texas and Nebraska licence plates adorning them.

Holding hands they made their way up the stairs.

Against each other they were formidable. When they teamed up, they were a force nothing could reckon with.

He opened the door to his apartment, and they stepped inside, into the middle of a party. Together they stood, eyebrows raised, waiting to get noticed.

Their relatives appeared to be having a great time, there was music and drinks and food being passed around. Penny raised her eyes to Sheldon and stood to whisper in his ear. "You wanna back out and go over to my place and get carnal?"

An evil smile grew on his face as he looked down at her. She grinned back and pulled him back through the door, over to her place, locking the door behind them, before Sheldon took her in his arms and leaned her back against it...

The only person who noticed their departure was Leonard as he came out of the bathroom. He'd seen her whisper, he'd seen the smile they shared and by the look they had shared. He knew what that was. Hunger.

And something else too. Like they couldn't get enough of each other.

He sighed. He didn't need to ask any questions to know that Penny would never be his, had never really been his. He didn't even need to ask if they were really married.

It didn't matter.

They were happy.

As his eyes scanned around the room at the people he'd brought together, his eye was caught by a short girl, sitting in the corner, a cute red dress and curly blonde hair. She was staring at his white board with an awed look on her face.

He walked over, curious. "Do you like it?"

She tilted her head. "I don't know what it is."

"It's an equation." He sighed. "I'm trying to figure out how much energy it would take to blow up an asteroid heading to earth."

The girl reached out and grabbed him by the shirt, her eyes on his. "Like... BOOM?"

He stared at her and nodded slowly, watching a grin cover her face.

"I LOVE it when things go Boom." Her grip was like iron. "Do you have lasers?"

He smiled. "Lots."

Her eyes lit up. "Show me."

Across the room Howard and Raj watched silently.

"Huh. I guess his perfect match isn't a little old lady in the poorest part of China after all." Howard commented.

Raj just nodded and took a sip of the drink Missy handed him.

"Its alcoholic." She said, her fingers crossed behind her back. "Can you talk to me now?"

"Thank you." He smiled at her.

Howard rolled his eyes and smiled as Bernadette tiptoed into the apartment. "Sorry I'm late," She whispered, "We had a small issue at the lab, but don't worry, I washed my hands."

AN: The End! I would have loved to make it longer, but with xmas and company coming I won't be able to write for a little while, and I wanted this finished so I didn't leave you all hanging over the holidays. .. I hope you enjoyed the story!