When Sheldon went to work Monday, he was actually put out that no one noticed his wrist. Not Leonard during breakfast, not Mrs. Vartebedian to whom he waved, not the cashier at the snack cart from whom he bought Red Vines to use to gnaw out his consternation. He sat at his desk amazed by the blindness of people.

"How could not one person notice?" He wondered aloud. Sheldon was currently sporting a two inch by two inch grape juice colored bruise on the inner wrist of his dominant hand. The thing practically screamed "Look at me!" but people were apparently deaf as well as blind.

He received some satisfaction later in the morning when he was finishing up in the restroom as Dr. Gabelhauser was entering it. Sheldon was engaged in a hand-scrubbing that would put a surgeon to shame. Dr. Gabelhuaser came in to check his hair.

"Dr. Cooper." He greeted.

"Dr. Gabelhauser." Sheldon rinsed off the lather and stepped away from the sink. The fixtures were all on sensors and he loved the thrill that his hands would remain pristine until he got back to his office. Sheldon held his hands up just like a surgeon would as he approached the paper towel dispenser.

"Dr. Cooper, what happened to your wrist?" Dr. Gabelhauser had caught sight of it in the mirror. Sheldon kept his back to his superior as the dispenser rolled off a towel. He dried his hands and between each finger then used the towel to pull the door open.

"I had an encounter with a rabid wolverine." He replied, exiting the bathroom.

XXXX

Howard, as always, did not disappoint. Leonard would not be at lunch because he was filling in for Leslie Winkle at her afternoon undergraduate seminar. Raj was seated to Sheldon's right diligently finishing his lima beans. Howard slid into the seat across from them.

"Do you guys want to checkout a movie tonight?" Raj suggested. Sheldon took in a mouthful of chicken.

"I can't," Howard groaned. "I have to take my mother shopping for a new girdle. She goes through them faster than sand through the hourglass figure she never had."

"Is there anything good playing?" Sheldon wiped his mouth with his napkin. Howard continued murmuring to himself.

"We should invent some kind of super elastic that would allow a woman to adjust a girdle just like a bra." He looked at his companions. "We could have a niche market, boys."

"Impossible." Sheldon put down his fork and automatically gestured with his right hand. "The properties of elastic imply…"

SHELDON COOPER, IS THAT A LOVEBITE ON YOUR WRIST?"

It seemed the entire cafeteria came to a stand still. Howard had actually stood up, knocking his chair backward and pointing a finger accusingly at Penny's calling card. Sheldon's right eye twitched; he'd actually forgotten about his wrist for a moment.

"Holy crap, dude!" Raj exclaimed. "Were you attacked by some sort of mutant vacuum cleaner?"

"Sheldon, I'm still waiting for an answer." as was half the Caltech lunchroom.

Sheldon picked up his tray and rose form the table. He recalled Penny's words: Be mysterious.
"Howard, everybody knows there are vampires in California." and he walked off.

XXXX

Penny skipped into 4A on Sunday at exactly 8:50PM. Her face fell when she saw Sheldon at his whiteboard instead of perched on the couch
"Hey, Sheldon."

He threw a quick glance over his shoulder.
"Good evening, Penny. I trust you are here to watch that travesty of a TV series again." Sheldon turned back to the triangles, curves and strange-looking Z's on his board. Penny pursed her lips. Odd.

"Well, yeah. I told you I would be when you asked. Aren't you going to watch it with me?" She had made her way to his board. Sheldon stopped writing when the vanilla sugar smell filled his nostrils. He turned to face her; his right hand hovering in the air between them.

Penny's eyes flicked to his wrist. The mark now encompassed a rainbow of hues. Yellow around the edges blending into soft violet to cranberry with a dark red center. She took Sheldon's uncertain arm and locked eyes with him. The blue took her breath away. Usually it was bright, searing, electric. Now, it was dark, so dark she couldn't discern his pupils. Slowly, she raised his wrist to her mouth and gave the hickey a deliberate, flat-tongued lick. Sheldon shuddered.

"Don't you want to know what happens next?" Penny's voice was husky. The physicist licked his lips.

"Very much so."

"Then what's stopping you?" Penny nipped his sore wrist and his arm jerked away.

"Hey Penny! Do you want me to make popcorn?" Leonard walked into the living room from the hallway. Penny quickly stepped back.

Fuck !

Leonard veered into the kitchen and began making popcorn.

"Sheldon, are you watching TV with us?" He asked.

"I don't think so." He physicist replied, returning to his board. Penny frowned. That wasn't supposed to happen. She walked over to the couch and placed herself in Sheldon's spot.

"Penny, that's my spot."

"You're not using it.' She replied and wiggled her bottom more firmly into the cushion. Popcorn punctuated the air and Sheldon slammed the cap onto his marker and faced Penny.

She was prone across the two cushions. Her pink shorts had ridden up to just below the curve of her rear. Sheldon chewed on his lower lip before shooing her over and seating himself.

"Your show is on." He indicated the clock which read 9:02. Penny clicked the remote and the words of the theme music filled the air.

"Before the night is through, I want to do bad things with you."

Sheldon let out a breathy laugh.

XXXX

Leonard joined them on the couch. Penny was now sandwiched between the roommates.

"So, what is this show about?" Leonard wanted to know. Sheldon responded.

"It appears to be based on the premise that vampires, ridiculous ones at that, now slake their thirst…"

Penny clapped her hand over his mouth. "It takes place in Louisiana," She told Leonard. "Vampires have revealed themselves because the Japanese have…" She stopped in her explanation. Sheldon had just drawn a single line up her palm with his tongue. Leonard looked at Penny expectantly.

"Sorry," she stammered, "I lost my train of thought. Anyway, Sookie, the main character, is a telepath." Sheldon took the flesh of her palm between his teeth and stroked it with his tongue. Penny's temperature shot up and there was liquid between her legs.

"Just watch it." She gasped, pulling her hand away from Sheldon

XXXX

Twenty minutes into the hour long show, Penny's fingernails caught the mark on Sheldon's wrist. She looked up at his profile and saw his right eye move the tiniest fraction. A sinister smile darted across her face as she looked back at the screen. Leonard was too busy shoveling popcorn into his mouth to notice either of them, but if she kept staring at the taller man, he would definitely notice something was up. So, she had to do all of this by touch and touch alone.

She dug her fingernail into Sheldon's wrist a little harder, not hard enough to draw blood, but she did feel his arm tense. Turning her body so that Leonard couldn't see her arm, she trailed her nail up Sheldon's forearm and into the crook of his elbow. She relieved some pressure and lightly grazed his arm back down the other side, all the way down to his hand which was resting on his lap dangerously close to his crotch. Sheldon didn't budge, but she could feel him shivering beside her. Before bringing her hand back into her lap, she lightly skimmed the back of her hand against his, and casually brushed his thigh.

"Sheldon, are you okay?"

Leonard's voice made Penny jump and she quickly looked up at Sheldon who's eye was twitching so ferociously she thought he might be having a seizure. Penny turned and looked at Leonard who seemed to be focusing solely at his roommate. He obviously didn't see what she was doing just moments before.

"Leonard, Sweetie, do you have any RC Cola?"

Both physicists looked at Penny as if she had lost her mind.

"No," Leonard answered. "Why would we have RC Cola?"

"I don't know, but I really have a craving for it. There's something about vampires and RC Cola." Penny looked at him through her eyelashes and licked her lips.

"Th-there's a corner store about a block away that sells things like that," Leonard stammered. "I could go check?"

"That would be so great! Thanks, Sweetie." Penny gave him a wink. It didn't take long for Leonard to jump up, grab his keys and run out of the door, slamming it behind him.

Turning around to face the other physicist, Penny found him staring back at her with a mix of contempt and anticipation.
From the TV, a heavy bass beat was thumping undercut by moans of passion. Bill had just rescued Sookie from werewolves and she was expressing her gratitude by riding him fiercely. Sheldon flicked his eyes to the screen for just a second- long enough for Penny to catch the reflection of the action on his corneas. God, she loved this show!

Penny grabbed Sheldon's arm and placed her tongue on his lovebite. She licked the inside of his arm all the way up to the edge of his pushed up sleeve, moaning as she did so. Sheldon's breathing quickened and he let out a shuddering sigh. Without warning, Penny lifted her hand and raked her fingernails across the inside of Sheldon's forearm. Hard.

Sheldon let out a stifled yell and looked down at his arm. Penny gasped as she saw traces of blood swell from under the scrapes. Her eyes went wide and she looked up at her neighbor. An apology died on her lips. There was a look on his face she had never seen before. His blue eyes stared icily at her through hooded lids. His head was tilted down and his chest was rising up and down in an almost exaggerated fashion. He looked like a predator ready to attack his prey. She looked down and saw him lick his lips.

A sound at the door caused the spell between them to break and they both turned to see a sweaty, panting Leonard bursting into the apartment.

"No…RC…Cola….Sorry," Leonard wheezed.

Penny hoped her "put out" look came across as disappointment at Leonard's announcement.

"I'll see what we have in the fridge." Leonard said when he got his breath back and made his way into the kitchen.

Penny turned and looked at Sheldon. His eyes were flitting back and forth between the kitchen and her and his breathing had become faster and louder. She wondered why he was suddenly acting like that. Had she broken him? As soon as Leonard stuck his head in the fridge, Sheldon leant over Penny, brushed her collar down toward her shoulder and sank his teeth into her neck. It took every ounce of self-control she could muster not to cry out at that moment. Whether she wanted to cry out in shock or in pleasure, she wasn't sure. Sheldon didn't bite hard, but she could still feel a slight ache in her muscles that were clamped between his teeth. Any pain was subdued by the feel of his tongue flitting on her skin as he continued to bite down. She had to bite her own lip to keep from making any sounds.

"While I'm in here, do you guys want anything?" Leonard called from behind the refrigerator door.

As quickly as Sheldon pounced on her, he was back in his own spot, sitting up straight and eyes glued to the television as if he hadn't just thrown everything she ever knew about him out of the window.