The Highlighter Catalyst

Silence filled apartment 4B as Penny leaned against the counter and sipped her coffee, not yet awake but definitely not asleep. She stared blankly at Sheldon, watching his yellow highlighter move quickly from left to right. He was so fully engrossed in what he was doing and Penny suddenly felt as if she had to do something about that. There's nothing like a cup of coffee and a battle with Sheldon to get your blood going in the morning.

"Watchya doin'?" she asked in a bubbly manner that she didn't actually feel. She was an actress after all.

Sheldon rolled his eyes, but continued highlighting. "I'm reading an interesting and brilliant article which illustrates the improvements of string theory on gauge theory in reference to the Theory of Everything, and I'm highlighting the important information" he stated out of the corner of his mouth. She could detect the hint of annoyance in his voice, so naturally she pushed further.

"What's gauge theory?"

Sheldon sighed. "In layman's terms, gauge theory is used to explain the underlying interactions between quarks and gluons and other subatomic particles."

"Oh. What are quarks?"

Sheldon glared at her. She had him where she wanted him.

"Okay, okay. Sorry." She finished her coffee and plopped down on the couch next to the physicist. She leaned in closer to look get a look at the article. "Hey! It says it's by Dr. Sheldon Cooper, PhD."

"I did say it was interesting and brilliant, didn't I?" Oh yeah, she's getting to him.

"Why are you highlighting everything?"

"Because it's all important," he said through clenched teeth.

Penny leaned as close as she could to the page, so close she could hear his teeth grinding. She then paused for dramatic effect. "What's string theory?"

Sheldon dropped his article and highlighter and jumped up. "Good Lord, woman!" he squeaked. Penny picked up the highlighter but allowed him to continue. "You have lived across the hall, familiarized yourself with our personal space, insisted on dating Leonard despite warnings of ultimate doom, took pages of notes on Physics lesson I personally imparted unto you…" Penny stood up in the middle of his tirade and faced him. She was standing quite close. Sheldon faltered for a second, but only for a second.
"…And through all of this you never once picked up on any minute detail pertaining to string theory?" He finished strongly and glared, red faced and out of breath, at his neighbor.

"Nope." Penny said popping the p as she lifted the highlighter and left a small yellow mark on the end of Sheldon's nose.

The apartment was silent once again, but the electricity was deafening.

"You wrote on me!" Sheldon exclaimed. "You actually wrote on me!" His voice was full of shock.

"Correction," she stated matter-of-factly. "I marked you. I didn't actually write anything." She smirked at him, daring him to argue.

Instead he turned on his heel and marched over to his whiteboard and picked up his black marker. At first Penny thought he was going to give her an illustrated lecture on different styles of writing, but his intentions became clear as he took a step toward her. She turned and ran behind the sofa, but his long legs quickly caught up with her. Before she knew it, she was sporting a big black mark on the side of her face.

"You geeky bastard!" She shouted and added another mark to Sheldon's forehead. He didn't even hesitate before writing on her chin. She reached out to do the same to him, but he caught her arm. His grip was stronger than she would have guessed as she struggled to get free. Penny tried to kick his legs, but he anticipated her move and blocked her with his knee. Losing her balance, she tried to grab his other arm to steady herself. On her way down, she marked his forearm and she fell backward, causing Sheldon, in his shock from being marked again, to fall with her.

They lay side by side on the floor out of breath. Penny started to giggle but the laughter died on her lips when she saw Sheldon staring at her, a strange look in his eyes. Silence once again fell over them and they leaned toward each other. Penny looked down at Sheldon's lips.

"You've got something right there," she said softly and brought the highlighter up and drew a yellow line down the middle of his lips. The fact that Sheldon didn't react shook Penny back to reality. "You should probably wash that off," she said as she got to her feet. Sheldon stayed on the floor and watched her as she went quickly back to her apartment.

Sheldon stood up, walked to the bathroom and washed away the yellow marks that peppered his face and arm. He left the one on his lips until last.