A/N My first BBT fanfic, so please go easy on me. I've been watching the show a lot lately and realize I've become a little obsessed with it, so I thought I'd write a story. Sheldon is my absolute favorite character, I love his awkward geeky personality. Here are the pairings:

Penny/Leonard

Bernadette/Howard

Raj/OC

Amy/OC

Sheldon/OC

Chapter One

Penny was in the middle of folding laundry, humming to herself, when suddenly.

*knock knock* "Penny." *knock knock knock* "Penny." *knock knock knock* "Penny."

Great. "Coming, coming, coming!" Penny set down her white laundry basket and opened the door to see Sheldon, dressed in a yellow T-shirt with long sleeves and jeans, standing before her. "What's up?"

Sheldon took a deep breath. "Um….I have an issue that regards attention immediately."

"You mean you have a problem?" Penny translated. Although she'd known Sheldon for the longest time, sometimes she still couldn't understand what her nerdy friend was saying.

"Exactly." Sheldon nodded frantically, then continued, "Leonard has a cousin and is inviting her over tonight."

"Yeah, what's the problem with that?" Penny crossed her arms over her chest, leaning against the doorframe.

"He wants me to be...intimate with her." Sheldon looked horrified at the mere thought of it.

"So, what's the big deal? You're not with Amy anymore," Penny said, then felt guilty for reminding Sheldon of his painful breakup with his off-and-on girlfriend Amy Farrah Fowler.

"That's my point precisely," Sheldon told her, growing more and more frantic. "She's coming at five, and I need you to help me get rid of her."

"Slow down, Sheldon," Penny told him. "I'm not going to help you get rid of her."

"Why not?" He stared at her in shock, as if he'd been asked the most disturbing question in the world.

"You need to socialize, Sheldon," Penny said slowly. "Breakups can be very painful, and we all know-"

"I'm not sad." Sheldon looked puzzled over her predicament.

"Sheldon, you got twenty-three cats." She counted on her fingers.

"But I only kept one," Sheldon protested, holding up a single finger for emphasis.

"Sheldon, honey, why don't you just give her a chance?" Penny pressed on. This wasn't going to work. "I mean, you may like her. Even if not romantically, you can still be friends."

"Great," Sheldon muttered, giving in. "I'll have to stay up all night talking about unicorns and menstrual cramps."

Penny slammed the door in his face.

"Sheldon, relax," Leonard said, grabbing the remote from his annoying roommate. Since the news of Katie's arrival, Sheldon was seemingly agitated, showing a sign of emotion- a not-so-Sheldon characteristic that was beginning to worry Leonard.

"She'll be here any minute." Leonard swatted at Sheldon with the remote when he started to push the recliner in and out repeatedly, a distraction for his distress.

"Even better!" Sheldon put his hands over his head and started muttering to himself.

Leonard squinted at Sheldon through his glasses. "What the hell are you doing?"

"I'm hiding," Sheldon said, looking pleased with himself.

"I can still see you there," Leonard sighed. He really didn't get Sheldon at all sometimes.

"No you can't-"

"I can," Leonard snapped. What was the big deal? A girl was coming over, it was no need to have a mental breakdown over something like that.

"Drat," Sheldon muttered, more to himself than to Leonard.

There was a knock at the door.

"That'll be her!" Leonard glared at Sheldon. "For god's sakes, act normal. In other words, don't be yourself."

"Got it." Sheldon was halfway under the couch, his head hidden and his buttocks facing Leonard.

Leonard sighed and rolled his eyes, then headed to the door. He opened it.

Katie immediately gave him a hug. "Lenny!" He smiled at the all-too-familiar childhood nickname. He and his cousin Katie had always been very close growing up, a result of her parents dying and moving in with Leonard's family temporarily.

The last time he'd seen her was at high school grad, but she hadn't changed. She still had the same pixie cut, bright red hair, but with a blue streak across the bangs. She wore glasses, a T-shirt that said "MORE COWBELL" with a cow on it, and faded jeans. A bit nerdy, but mature at the same time.

"Well, what are we just standing here for?" Katie barged in, pushing him aside. "Wow, nice place."

Leonard chuckled to himself. That was Katie- always jumping into things, and this time literally.

"I'm not here," Sheldon's muffled voice came from underneath the sofa.

"Is he...okay?" Katie asked, staring at part of Sheldon in wonder.

"Yeah, he's fine," Leonard said. "He's just acting a little weird lately. Sheldon, get out from underneath the couch and say hi."

Sheldon peeked out momentarily, and said, "Hello" then ducked back into his obvious hiding spot.

"Ignore him," Leonard scoffed, leading Katie into the kitchen.

"What's wrong with him?" Katie and Leonard sat down at the table.

"Everything," Leonard mumbled, and Katie raised her eyebrows at him. "He's just being weird, that's all."

"Does he not like girls, or something?" Katie questioned, drumming her blue nails on the table.

"No, it's more like he doesn't like people," Leonard corrected. "It's been like that since I've known him."

"He's your roommate, am I right?"

"Correct," Leonard said.

There was an awkward silence. Leonard then asked, "So, how's life?"

"It's okay, I suppose," Katie shrugged. "The usual. I'm trying to get into school."

"Really?" Leonard perked up at the mention of studying. "What school?"

"The one you're going to, actually," Katie said. "I wanna study writing."

"Writing? That's great!" Katie had always written short stories as a child. But he never knew she'd go through with it as an adult, too.

"Yeah, I-" Katie was interrupted by a loud bang. "What the hell was that?"

They darted into the living room. Sheldon was lying on the floor with the lamp lying on top of him.

"Sheldon," Leonard moaned, mentally face-palming.

"Are you okay?" Katie knelt down next to Sheldon, extending a hand. He stood, ignoring the gesture.

"The lamp did not certainly defy gravity."

Katie blinked at him. "What?"

"Well, you see…." Sheldon began, but Leonard pushed him onto the couch. "Okay, big boy. Anyone want some drinks? I could order pizza or something," Leonard said quickly.

"Pizza? Great!" Katie perked up at the mention of her favorite food.

"Great, I'll go order it," Leonard announced, heading into the kitchen, carrying his cell phone.

"Hi, I'm Katie," Katie said, sitting down next to Sheldon. Sheldon sat in his spot. "Dr. Sheldon Cooper," he managed. God, was he beginning to turn into Raj?

"Nice to meet you," Katie said. An awkward pause.

"Your full initial is Katherine, may I presume?"

"Yes," she looked puzzled.

"Oh." Sheldon nodded. "Alright, then."

And that was that. At least, until the pizza got there.

"No, Sheldon, we do not want to watch another episode of The Flash," Leonard complained as Sheldon picked up the DVDS off the floor.

"But why not?" Sheldon squinted at his friend. "I sit through your TV programs, and do I complain?"

"Loudly," Leonard said.

"No. So, you shall do the same for me."

"Hey, I like The Flash," Katie said, smiling. "He's cool."

"Oh?" Sheldon perked up like a happy puppy. "Are you a fan of other Marvel DC comics?"

"Yes!" Katie snapped her fingers. "Recently I went and saw Captain America."

Sheldon, eyes wide, started to describe plots and favorite villains of super hero movies.

Katie grimaced. "Sorry," she mouthed to Leonard.

Leonard smiled thinly. It was going to be a long night.