Disclaimer: I do not own The Big Bang Theory or any of its characters. If I did Sheldon/Penny would be so on. I do however take responsibility for any and all science errors.

AN: Spoilers up through all of season 3. Events from season 4 may work their way in as well so if you aren't up to date then you may be spoiled.

AN: Thank you to everyone who has read and reviewed this story! Your kind words have been very motivational and I hope that I can live up to your expectations. I would like to add a special thank you to shadynaiad for being so supportive and putting up with all of my fanfiction related angst even though she hasn't seen much BBT.

The Emotional Attachment Determination

Chapter 2: The Laser Tag Substitution

Penny stood in Sheldon and Leonard's kitchen drinking coffee and fiddling with the edges of the contract sitting on the island in front of her. She hadn't slept well the night before, her mind troubled by the contract and what it symbolized. She knew that she needed to talk to Sheldon about it but she had no idea how.

A door opened in the hallway and she saw Leonard stumble sleepily into the kitchen.

"Penny?" He asked, rubbing his eyes. "What time is it?"

Penny glanced over at the microwave clock. "6:00."

"In the morning?" Leonard asked blinking at her in confusion. "What are you doing here at 6:00 in the morning? What are you even doing up?"

"I couldn't sleep." She answered. "And I was out of coffee."

"You not able to sleep?" He asked incredulously. "I've seen you sleep through movies, car rides, and even epic physicist brawls."

Penny stuck her tongue out at him.

Leonard grinned. "Seriously though, you okay?"

"I'm fine. Just had a lot on my mind." Penny said glancing down at the contract.

"What's that?" Leonard asked following her eyes.

"It's nothing." Penny said trying to tilt it away from Leonard's curious gaze. As much as she wanted to talk to somebody about the whole situation she knew that Leonard would treat it like a joke. "It's a script for a pilot that I'm auditioning for."

"Oh." He said moving away and pouring himself a cup of coffee. "Well I'm sure you'll do great."

"So what's going on today?" Penny asked trying to take his attention off of her.

"We were supposed to play paintball." Leonard said sipping his coffee and leaning back against the counter. "But it's been raining all night so laser tag is our backup plan."

"That sounds like fun."

"Yeah." Leonard said. "At least it won't sting so badly when I get shot."

Penny laughed.

"Hey," Leonard said suddenly looking insecure. "Would you like to come? We could always use someone who can actually shoot to help us beat the chemistry department."

Penny frowned. She was tempted to say no so that she could avoid Sheldon for a while longer. She had come over to their apartment with the intention of talking to him when he got up to watch Doctor Who, but she still wasn't sure what to say. On the other hand, running around and shooting people sounded appealing at the moment and it wasn't like she had anything better to do. Not since the Cheesecake Factory had decided to cut several of her shifts, including all of her tip-heavy Saturday hours.

"I guess." She said with a shrug. "But if you're bringing me in as the muscle then I'm not paying."

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"Isn't it bad enough that I had to spend Vintage Video Game Night watching that poor excuse for a Star Trek movie? Now you're telling me that instead of our normal Saturday paintball match full of strategy and true simulated warfare, we have to go play laser tag?" Sheldon asked indignantly from his position on the couch.

"If you want to go crawl around in the mud by yourself go for it." Leonard said. He gestured at Howard, Raj, and Penny who were standing near the door. "We're going to go play laser tag with the rest of the university."

"But none of our strategies will be applicable. The arena is indoors and dark not to mention much smaller than a paintball field. It will take hours to come up with an alternate strategy taking into account all of the new variables." Sheldon complained.

"Or you could just hide and shoot." Penny offered cheerfully.

Sheldon glared at her. "Strategy aside, I don't have a laser tag gun."

"No one does. That's why they rent them." Howard said in exasperation. "Even if you had your own gun it wouldn't be hooked up to their system."

"But I can't use a communal gun. Do you have any idea the number of people who use those guns? Who knows what diseases are waiting on those triggers?" Sheldon asked before answering his own question. "I do. Given the rather poor sanitary habits of children it can be assumed that those guns are covered in E. coli, Salmonella, Staphylococcus aureus,influenza, and any number of rhinoviruses and coronaviruses. No thank you."

"Okay." Howard said opening the door. "We tried. He's not coming."

Sheldon watched Howard leave the apartment followed by Raj and Leonard. It would take an idiot not to notice the relief on their faces as they left him behind and Sheldon Cooper was definitely not an idiot. He frowned, trying to ignore the slight discomfort in his chest. He should be used to it by now. After all very few people truly appreciated him the way they should.

He turned his gaze to Penny, who hadn't moved. She was staring at him with a thoughtful look on her face. "How about if I bring a packet of bleach wipes?"

He stared at her for a moment before feeling the corners of his lips turn up slightly. "That might be acceptable."

"Well then hurry up." She said. "If we get there early maybe you can come up with a strategy before we start."

"Oh I don't think so." Sheldon said standing up and quickly getting his jacket from the closet. "The amount of time it would take to come up with a workable strategy for the entire physics department-"

"Why don't you just come up with one for us and let the rest of the physics department worry about themselves?" Penny asked as she dug her key out of her purse.

"That isn't a very good way to beat the other departments." Sheldon pointed out. He looked behind her at his three irritated friends and realized that he didn't particularly care if they spent the entire afternoon as target practice for the chemistry department. "But perhaps an individual triumph would be enjoyable."

After Penny retrieved the bleach wipes from her apartment the five of them headed downstairs. Sheldon was a bit concerned about the efficacy of the bleach wipes as they were a much lower concentration than he normally used when he cleaned but he supposed that they would probably kill most of the organisms that he was likely to be exposed to.

"You had to convince him to come didn't you?" Howard whispered to Penny a few steps down from Sheldon. If his hearing wasn't so sharp he wouldn't have heard the low whisper.

Sheldon watched as Penny turned and gave Howard a glare that he truly thought would cause Howard's head to explode. He was a bit disappointed it didn't work but it did make Howard move as far from Penny as he could in the stairwell. Sheldon once again felt his lips tug slightly up into a grin. It was nice having a best friend that actually wanted him around.

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"Sheldon, I promise you that the gun and vest are clean. " Penny said, looking tiredly down at the pile of used bleach wipes. She couldn't help but think of the five dollars wasted on cleaning supplies that would never be used in her apartment.

"You don't exactly have the best track record regarding contagions." Sheldon said look at her a bit suspiciously.

"You're right, Sheldon." Penny said rolling her eyes. "I brought you all the way down here and spent the last fifteen minutes helping you scrub everything down just to make you sick. Maybe I should have just hugged you back in the apartment and saved all that time."

Sheldon huffed and glared at her indignantly.

"Now if you're done being crazy, we need to go enter our names or won't be able to take part in the first round." Penny said, smiling to take the sting out of her words.

Sheldon wordlessly put on his vest and holstered the gun. Together they made their way to the line at the desk.

"Well, well, well." Penny heard a particularly irritating voice say from behind her. "If it isn't Dr. Dumbass and Barbie."

"Winkle," Sheldon growled. "I thought you were too busy getting nowhere with your inferior research to take part in these little competitions this year. Have you managed to lose all of your funding yet?"

Penny turned to look at the annoying brunette behind her. She had never liked Leslie Winkle. At first she was jealous because Leonard had dated her but after a while she realized that the girl was just mean. Mean and selfish.

"Nope," Leslie said with a smug grin. "I just got a new grant allowing me work with Martin Bojowald on his Loop Quantum Cosmology research. How about you Dr. Dumbass, any progress with your little dark matter research? Found any can openers?"

As soon as Leslie mentioned can openers, Sheldon jerked as if he had been physically slapped. It took Penny a moment to remember that the guys had messed up Sheldon's research in the Arctic with a can opener. Penny didn't know how Leslie knew about the prank but it made her angry to see Sheldon so clearly upset. It called to mind the day when he had first found out that all of his discoveries had been a lie.

Without even thinking, Penny stepped in front of Sheldon and glared at Leslie.

'You're just jealous that Sheldon is so much smarter than you. He's smarter and more pleasant to be around than your bitchy ass. So back off!"

"Oh I'm so scared Barbie!" Leslie said sarcastically. Nevertheless, she quickly walked away.

Penny stared after Leslie's retreating back wondering what had come over her. It wasn't the first time she had confronted a bully, growing up on a farm in Nebraska she had learned how to be tough at young age, but it was the first time in quite a while that she had seriously been ready to fight someone. And there was no doubt in her mind that if Leslie had stayed she would have punched her. The image of Sheldon hiding in his room so hurt and embarrassed by what his friends had done to him had just appeared in her mind and all she could think was that she couldn't let that happen again.

"Bitchy ass?" Sheldon inquired, shaking her out of her thoughts.

"It's at least as clever as Dr. Dumbass." Penny said defensively turning back to look at her friend.

"I'll grant you that." Sheldon said moving forward in the line. "And I do find the description satisfyingly appropriate."

"How did she know about the can opener?" Penny asked hesitantly.

Sheldon's face darkened and he gestured to the corner of the room where Leonard, Howard and Raj were listening to an agitated Leslie. "I assume one of them told her. Either out of amusement at their prank or as an attempt to curry favor for coitus."

"That's awful." Penny said disgusted both at the behavior of Sheldon's friends and at the matter of fact way that he just seemed to accept that kind of treatment. It was suddenly becoming clearer to her why she was the one with a Best Friend Contract waiting for her at home and not one of Sheldon's other friends. She could also understand why he felt the need for a detailed contract to protect himself.

She wasn't under any illusions about Sheldon. He often deserved the sharp retorts and frustrated anger of his friends. He constantly belittled them and was nearly impossible to live with but that didn't excuse their behavior. There are lines that you don't cross and screwing with someone's work was one of those lines. Penny felt guilty for not taking it as seriously as she should have last year. It was becoming obvious that it wasn't something that could just be brushed off and would likely follow Sheldon around professionally for some time to come.

They were both relieved when they finally reached the front of the line and were able to give their code names to the man running the game.

"Okay Queen P and Sheldor, you'll be entering from the third door. Game starts in five minutes." The man said with a bored yawn.

Sheldon turned to her as they made their way to the group of people waiting at the third door. "We need to find a defensible position on the second level. The high ground will give us the advantage, making it harder for others to attack us and allowing us to act as snipers."

"Are you sure we can't just track Leslie Winkle down and kill her as many times as we can?" Penny asked.

Sheldon gave her an exasperated look. "I would rather take her out from above when she is least expecting it."

"Okay, okay, whatever you say General." Penny said with an exaggerated salute.

Two hours and five games later Penny was tired. She and Sheldon had found a corner where two walkways intersected against an outside wall that between the two of them they had managed to keep defended. They had stayed close, each facing down a different walkway keeping attackers away and taking shots at the people running beneath them. A part of her would have preferred to run around a bit more maybe take it less seriously but there was also something to be said for winning. And Penny didn't have any doubts that they would have some of the highest scores. After all they had both learned to shoot at an early age and that experience coupled with Sheldon's sniper strategy and she doubted many people would beat them.

When the lights came on after the fifth and final game, Penny and Sheldon made their way slowly out of the arena and joined the crowd gathered around the giant television screen displaying the scores. The highest score for all five games combined was Sheldor followed closely by Queen P.

"Yes!" Penny exclaimed turning to Sheldon excitedly. She held up both of her hands to give him a high five.

Sheldon stared at her hands for a moment before rather awkwardly hitting the tips of her fingers with his own. His face twitched when their hands made contact and he quickly withdrew his, scrubbing them against his plaid pants.

"Close enough." Penny laughed. "Come on I see the guys over there."

"You killed me twenty times." Leonard whined to Penny as soon as she walked up. He waved the print out he was holding in Sheldon's direction. "And you killed me seventeen times."

"Only seventeen?" Sheldon asked. "I counted at least 28 times that I fired at a man with your hobbit-like physique."

"It was dark in there, maybe you missed." Howard said.

"Unlikely, my father regularly took George and me out shooting rats at night when we were children. He called it 'spending quality time with his sons,'" Sheldon said a bit of his Texas accent coming out. "A much more likely scenario is that I mistook a short-haired female for Leonard."

Leonard glared at Sheldon. "Why were you aiming for me anyway? We were on the same team. You might have gotten the highest score but the chemistry department still won."

"Penny and I decided that an individual victory would be more fulfilling." Sheldon replied.

"Oh did you?" Leonard asked looking accusingly at Penny.

Penny shrugged. "I'm not a member of the physics department. Can we just go home? I'm tired."

A short, tense car ride later, Penny was at home curled up in bed for a much needed nap. As she pulled the blanket up over her head to block out the sun she realized that she still hadn't talked to Sheldon about the contract. She had spent most of the day with him but they hadn't had any time alone for her to bring it up and now she was much too tired to deal with it. Even so, she didn't want to wait too long to talk to him and after a moment of thought she had the perfect solution. Penny realized that she knew exactly where Sheldon would be at 8:15 on a Saturday night which just gave her enough time for a four hour nap.

If she was lucky she might even be able to kill two birds with one stone and get her laundry done. Penny smiled as she drifted off to sleep.