Sheldon tried once more to sit up, but he fell back to the bed. Through the sleepy haze, he found that his wrists and ankles had been tied down. He really needed to train himself to be a lighter sleeper.

"Bungee cords," Penny answered his thoughts. "I found them in your closet."

Sheldon bit his lip trying hard not to say anything. Leonard was in his room on the other side of this wall, and he was not nearly as heavy of a sleeper as Sheldon. He squinted in the light of the beam, a bolt of fear tinged with excitement traveled down his spine. When he felt Penny's hand on his thigh, he dropped his head back into his pillow with a repressed sigh.

He didn't have any idea what she was doing or what she planned to do. Not knowing what was going to happen, any change in his routine, usually set him into panic mode. But he had gotten used to the spontaneity that was Penny. She infiltrated his life and every time he turned around, she was there upsetting the delicate balance and disturbing the order he made for himself.

What she was doing to him now, what they had been doing for the past few days, went beyond anything that he had experienced from her before, and as he felt her hand rubbing up and down the inside of his thigh, he had to acknowledge that, once again, she had achieved victory in their constant battle for dominance.

"Penny," he whispered, not sure how he was going to end the sentence. He either wanted to tell her to stop or to tell her to keep moving, just a little higher.

"I said not a word," she answered sharply. "I have a scarf here that would make a perfect gag. Don't make me use it."

Sheldon immediately closed his mouth, afraid of whatever god awful and dirty piece of cloth she was threatening him with. She turned off the flashlight and moved up, kneeling on the bed with his stomach between her legs. He blinked a few times, trying to see in the dark, hoping that the residual light stamped into his retinas would fade so that he could see her face.

Blond hair suddenly curled onto his cheeks and nose and he felt Penny's tongue trailing along the curve in his neck. The hair tickled and itched his face, but his hands were tied. All the could do was turn his head away from it, leaving his neck further exposed to whatever deviousness she was planning.

He held his breath when he felt the tendons in his neck suddenly between her teeth. He thought about what he did to her neck earlier that day. He remembered seeing his mark on her, marring her perfect flesh, and for a moment, he felt the pangs of regret. Everything he has done with her lately has been completely out of character and he couldn't understand why he was doing this. He turned his head even further, allowing her ample room to get her revenge.

But the bite never came. Instead, he felt her teeth grazing and lightly nibbling up his neck and behind his ear. All thoughts left his head when he felt her nip at his earlobe. His breath, which he forgot he was holding, left him all at once. He almost let out a pleading moan when she stopped suddenly, but when he turned to look at her, his eyes finally adjusting to the dark, he saw that she was taking her top off.

She didn't have a bra, so she was fully exposed to him immediately. His eyes went wide, not so much in shock at seeing her breasts, but in surprise at his reaction to it. He felt himself harden at the sight of her nipples and he wiggled with impatience.

Penny smiled a wicked smile and placed her palms down on either side of Sheldon's head so that her chest was now inches above his face. He lifted up immediately and brought her right breast into his mouth. It was an awkward position to be in. His hands were tied to the posts of his bed and remained behind him, so he had to rely on his abdominals to hold him up. She must have known this because she sat up a little straighter, forcing him to lift up higher. In response to her mischievousness, he caught her nipple between his teeth and his tongue and lightly pulled. She gasped a little too loudly and the sound of her voice caused his hips to twitch.

He moved on to the other breast, but this time he lightly bit her nipple. Her gasp was louder this time and he paused for a moment to listen for any movement in Leonard's room. When he was satisfied that Leonard was not awake, he continued, feeling her shiver in his mouth. He let go of her suddenly and fell back into the bed, panting.

The room seemed much lighter now and he could see her face clearly as she ran her fingers over the scratches in his arm. He thought she looked sad, but he was never very good at reading emotions. At that moment, he wanted to kiss her. Gathering up all of his strength, he lifted himself up and touched his lips to hers.

Penny didn't hesitate to pull back. She immediately pulled herself off of him and slid off of the bed. Once again, Sheldon sank into his pillow and sighed. He heard a rustling beside the bed and turned to see what she was doing. He nearly yelled out when he saw that she had the scarf in her hand.

"No, Penny. No! I mean it. Don't you dare -" Sheldon whispered as harshly as he could. It didn't stop her, however, and she stuffed the scarf into his mouth and tied a knot at the back of his head. Sheldon tried his hardest not to think about the germs that were currently residing on the cloth that was in his mouth, which wasn't so hard once he felt her climb back on top of him. This time, they were crotch to crotch. When he felt her tongue in his ear, all bets were off. His hips bucked up and Penny accidentally let out a quiet cry of pleasure and surprise. They both quieted down and listened for Leonard, and Sheldon could feel the pressure and heat on him. When they heard nothing, they resumed their grinding.

Sheldon closed his eyes so that he could feel more of her, but she slid off of him. He wanted to ask her not to stop, but the cloth in his mouth prevented him from saying anything. Then her hands were untying the pull string of his pajama bottoms and Sheldon almost had a panic attack.

She slipped his pants down just enough and a muffled gasp escaped from behind the scarf when he felt her cold hands on him. His hips bucked uncontrollably as she slid her hand up and down. The effect she had on him was a hundred times more intense than any masturbations sessions that he had in the past. It seemed Leonard was mistaken when he referred to Sheldon as "semi-pro".

It didn't take long for him to come. His mind was swimming around too fast for him to notice the sticky mess they were making on his bed. He bit his lip to keep from crying out and he closed his eyes tightly, noticing the patterns of the starbursts behind his eyelids. While he shuddered in ecstasy, Penny undid the binding on his right arm and Sheldon felt a slight pain as the blood rushed back into his wrist. Keeping his other hand tied, she stood up and removed her shorts, then sat down on the bed next to him, her back to his stomach.

"It's my turn now," she whispered and spread her legs apart. It took Sheldon a few moments to understand what she was talking about, but even in a post-orgasmic haze, he was still a genius. Before he did anything, he moved the scarf out of his mouth. He would definitely make her pay for that. Bringing his free hand to a spot between her legs, he noticed how wet she was. A small part of him was disgusted; everything was so wet and sticky and messy. But that part of Sheldon wasn't in charge anymore. He was unsure of himself, but he knew what she wanted so he dipped his middle finger into her, exploring.

Her hips moved in time with his as he began to move faster and faster. When he slipped another finger in, her breath quickened. Sheldon filed that away for future reference. He wiggled his long fingers around, as if he were playing a piano, and enjoyed every moment of her squirming body against his. With each movement, he became more and more aroused, especially when her hips started rocking with his hand.

Then she began whimpering and his heart constricted - he wasn't sure if he was hurting her so he moved his hand away. He immediately regretted his decision when he felt her body still against his. If he was hurting her badly enough, she would have told him to stop. If he was hurting her just a little, well, he still had the taste of cloth in his mouth.

His thoughts were brought back to the action in front of him when Penny suddenly turned and brought her naked body over his again. Sheldon held his breath in anticipation and shook a little in fear of the unknown. He breathed out in relief and frustration when she moved her body down lower so that her legs were straddling his knees.

Sheldon groaned in shock when she licked his penis. He groaned even louder when she took him completely in her mouth. He was still sticky with…Sheldon didn't even want to think of that. Instead he closed his eyes and let himself feel the sensation of Penny. Her hand worked with her mouth up and down. His stomach clenched and unclenched each time she moved down. The feeling of her breasts hitting his thighs was too much and once again, Sheldon experienced the mind-blowing feeling of orgasm.

For a dreaded moment, he feared he had done something wrong. He knew her mouth was still on him when he ejaculated. When he managed to open his eyes and look at her, she was grinning at him and he figured it was something that didn't bother her, although he couldn't imagine why it wouldn't.

She shimmied her way up his legs and over his stomach and he could feel her warmth and wetness trailing up his body.

"Thanks for that," Penny breathed and poked his nose. For a fleeting moment, Sheldon imagined grabbing the back of her head with his free hand and kissing her, whether she liked it or not. But he didn't feel like tasting scarf again, so he just huffed instead.

Penny stood up and put on her clothes. "Goodnight, Sheldon," she murmured and headed toward the door.

"Wait!" Sheldon gasped. "You're not going to leave me like this." It was not a question.

"You have one hand free. You can manage." And with that she was out the door.

Swearing under his breath, Sheldon used what little strength he had left to lift himself and reach for the cord on his other hand. He managed to untie his arms and he bemoaned his tingling and sore wrists.

From outside of his room, Sheldon heard the front door close a little too loudly and not long after, heard the movement in Leonard's room he had been dreading all night. He quickly sat up and pulled the blanket over his body, making sure that every bit of evidence was covered just in time for Leonard's head to poke through his door.

"Is everything alright in here, buddy? I thought I heard a door slam."

"I just went to the bathroom," Sheldon answered in a clipped tone. He tried not to think about all of the bodily fluids that were swimming around on his bed and now on his blanket. Leonard returned to his room and Sheldon booted up his laptop. He wanted to be ready next time.

XXXX

"Sheldon! Dinner!' Leonard placed five containers of soup on the coffee table. The tall man appeared from his room. Sheldon held his arms stiffly to his sides. He walked to his spot and gingerly picked up his soup.

"Something wrong, Sheldon?" Howard noticed his restrained movements.

"My arms hurt." Sheldon replied while taking care not to bring his spoon to his mouth. Instead, he lowered his mouth to the spoon and the room was filled with a loud slurp. Raj and Leonard looked up, annoyance crossing their faces.

"Is that really necessary?" Leonard scolded. Sheldon lifted his head with the spoon poised at his lips.

"How else am I supposed to eat my soup?" He protested.

Penny opened the door and skipped inside. "What do I owe you, Leonard."

"6.95. You're awfully chipper this evening."

Penny waved Howard off the middle cushion and placed herself next to Sheldon.

She gave Leonard a slow, secretive smile then took the lid off the container and inhaled the spiciness of her minestrone. Raj let out a squeak when her hair drifted back over her shoulder to reveal a row of livid bruises along her neck and shoulder.

Howard arched an eyebrow. "Did you burn yourself with a curling iron?" . Sheldon spat soup out and Howard tossed him some napkins. "Too hot." Sheldon said, lamely.

"I bet." Howard snorted. Penny glanced at Howard and realized he knew full well that those marks didn't come from any hair appliance.

"No." She kept her voice even.

"Really? Interesting." Howard mused. "Sheldon was sporting a similar looking mark on his wrist about two weeks ago. Isn't that right , Sheldon?"

"Excuse me," Sheldon tried to push himself up off the couch without whimpering but failed. "I'm going to get a beverage. Anyone care for one?" He ignored Penny's look of concern and Leonard's puzzled frown.

"Are you sure you're going to be able to make it to the refrigerator?" Howard inquired.

With a final push, Sheldon unfolded his frame from the couch. He nearly bit his tongue off to keep from hollering from the pain. He walked into the kitchen and grabbed a can of Diet Coke from the shelf. Before shutting the door, he placed the cold aluminum to the rope burns on his wrists.