What have I gotten myself into?

The seven of them sat on the floor. Going clockwise, it was Raj, Howard, Bernadette, Penny, Amy, Leonard and finally Sheldon, who sat leaning against the couch directly below his spot, trying to remember how to breathe.

Inhale deeply. Exhale slowly. Repeat. Good. Just stay calm and don't panic, and for heaven's sake, do not faint.

"Okay, so the rules are simple," Penny said.

They had moved the table out of the way so that Raj's empty beer bottle lay directly in the middle of the floor, which was a travesty in and of itself for many reasons, but that was the least of Sheldon's worries right now.

"You take the bottle, spin it, and whoever it lands on, you have to kiss them," Penny explained.

"All right, now, quick question, what are the guidelines for the kiss?" Howard asked. "Closed lips only, or is a little tongue acceptable?"

There are going to be tongues involved? Oh, dear Lord!

Sheldon's breath hitched in his throat. From his peripheral view, he saw Leonard's head turn to look at him, but he kept his eyes solely focused on the dreaded glass beer bottle of doom. He needed to figure this out.

Mathematically speaking, after eliminating the person spinning the bottle, there was a one in six chance that the bottle would land on him. However, one also had to take into account the centripetal force of which the bottle moved, which required an entirely different formula. He knew he could easily do the math in his head to calculate that number. First, he would need to figure out the bottle's mass.

"Dude, you're married," Raj admonished.

"Yeah, dude," Bernadette sneered in a convincingly threatening tone despite her high-pitched voice.

"I was just asking," Howard said defensively.

"Let's keep 'em closed, okay?" Penny said. "Amy, you wanna start?"

"Heck, yes. The birthday girl wants some sugar," Amy said excitedly as she grabbed the bottle by the thicker end and spun it.

Sheldon's heart dropped.

No, I haven't finished my calculations.

The bottle quickly spun around several times, and as it slowed in motion, it just narrowly passed Bernadette and stopped to point at Penny.

"All right, girl kiss! Let's see some tongue," Raj said, and all six of them looked up at him with looks of deep shock and confusion. The wide grin on his face dropped. "What?"

Penny shrugged, and with that she turned her head towards Amy and leaned in, planting a closed-mouth kiss against her lips.

Sheldon's eyes widened. Penny is kissing my girlfriend. Penny is kissing my girlfriend. Oh, the humanity.

He'd seen this before, of course, but Amy hadn't been his girlfriend then. Now, it just seemed…wrong.

"Oooh," Bernadette said teasingly.

Penny pulled away and smacked her lips together, grinning lightly.

"That was quite enjoyable," Amy said seriously. She turned to Leonard. "You're a lucky man, Leonard."

"Uhhh…thank you?" he replied uneasily.

"Okay, my turn," Penny said. She grabbed the bottle and spun it with a fancy flick of her hand.

Oh, dear God, just think where that mouth of hers has been. Please don't land on me. Please don't land on me.

The bottle spun several times, this time slowing down to land on Bernadette.

"All right," Raj said, rubbing his hands together in glee. "Come on, let's show Big Daddy Raj a little tongue."

Bernadette and Penny looked at him. "Big Daddy Raj?" Penny asked, arching an eyebrow.

Raj shrugged, grinning. Bernadette then looked at her husband, who also shrugged.

"Just a little tongue?" he added, a pout on his face. "It's not like it's cheating, Bernie."

"You guys are pervs," Penny said.

"Give it to her good, bestie," Amy said encouragingly.

Penny glanced at Amy, unamused, before turning back to Bernadette. Penny let out a sigh. The two women simultaneously leaned forward, closing their eyes as their lips met. There was little to no movement from either of them, just two pairs of lips pressing together for roughly five seconds, until they both pulled back at relatively the same time.

How, exactly, do they both know the appropriate time to end the kiss?

Sheldon assumed that setting must be one of the factors taken into account. Being that this was a social setting, it was clearly inappropriate for a kiss to last longer than a few seconds. It was more casual, a peck on the lips that didn't last too long.

I think I can do that. As long as it's with Amy. But where exactly is the line drawn between kissing and "making out?" Is it the length? The hand placements? The use of…tongue?

Now fully immersed in his thoughts, Sheldon hadn't realized that Bernadette had spun the bottle until he looked up in time to see Bernadette and Howard kissing one another with much more passion. Bernadette's hand was on Howard's shoulder, while Howard's hand was pressed against her lower back. Howard's jaw stretched open, deepening the kiss in its intimacy.

Well, this makes my previous hypothesis moot.

Upon further consideration, though, Sheldon decided that perhaps it did make sense for a kiss to be more profound in this instance, as they were husband and wife, which clearly constituted for a much deeper level of physical intimacy.

Sheldon, will we ever have an intimate relationship?

A chill shot down Sheldon's spine as Amy's voice replayed in his mind. He squirmed on the floor. This was highly uncomfortable. He needed to figure out how to get out of this. He wanted to be more intimate with Amy, but not here, not now. He needed more time to think about it and figure out how to proceed.

Howard spun the bottle next, and the engineer's jaw went slack when the bottle pointed to Raj.

"Ooh, that's awkward," Leonard commented.

"I'll just spin again," Howard said, reaching for the bottle, but Bernadette's small hand stopped him.

"No, no, you know the rules," Bernadette said with a sickeningly sweet smile. "But don't worry, Howie. Kissing your best friend won't count as cheating."

Howard stared at his wife, growing paler by the second. For once, Sheldon was right there with him. Imagining kissing Penny or Bernadette was bad enough, but the idea of kissing one of his male friends was repulsive on a whole new level. Sure, the four of them had once slept together naked, but that had been for the sake of survival.

Raj, meanwhile, clearly too drunk to care, grabbed his best friend's face. "Come on, dude, it's not like we haven't done this before," he said, and before Howard had time to pull away, Raj dove forward, kissing the shorter man directly on his open mouth. Howard let out a stifled noise of protest and tried to pull away, but Raj just clutched him tighter, refusing to let go.

Sheldon wrinkled his nose at the sight. It was downright disturbing to watch.

Luckily, it didn't last long as Howard finally broke away, sputtering and wiping indignantly at his mouth.

"Hey, you don't have to act so disgusted," Raj said in a hurt tone.

"I'm not acting!" Howard insisted.

"Whatever, pretend all you want, but you know I'm a great kisser. It's all in the lip balm. That's why, back in New Delhi, all the women called me Soft Lips Koothrappali," Raj said, taking the bottle and spinning it while Howard continued to vigorously wipe his mouth on his sleeve.

I wonder which of us will be the next poor victim. Leonard and I are the only ones who haven't had to suffer the misfortune of kissing one of these…

His thoughts went blank. Raj's spin had landed on Amy.

"Ooh, now we're talking," Penny said.

"Yeah, lay a big wet one on her, Raj," Bernadette squealed.

Amy looked at Raj. Sheldon looked at him as well. Since the astrophysicist was sitting right beside him, he was able to distinctly see dilation in Raj's pupils, signaling a rush of adrenaline, which could've indicated a number of emotions. The likeliest was that he was either scared or aroused.

Either way, Sheldon didn't like it.

"No," he said, and instantly he felt everyone look at him, but he didn't care. He only had eyes for Amy. He could feel a strange tightening sensation in his throat as he looked at her. There was a stinging feeling spreading through his chest as well.

What is this feeling? I don't like it at all. How do I get it to stop?

"No?" Amy repeated.

"I won't allow it," Sheldon said firmly.

"'You won't allow it?' What are you talking about? You didn't say anything a moment ago when Penny and I kissed," Amy pointed out.

"That's entirely different," Sheldon countered. "Penny's a floozy who will kiss anybody."

"What? Hey!" Penny interjected.

"Sheldon," Leonard scolded.

"Besides," Sheldon went on, not letting either of them derail him, "after watching you two kiss twice now, I can plainly see that there is no potential for sexual arousal between the two of you."

"Whoa," Howard said, "Penny and Amy kissed before?" He turned to his wife. "What exactly do you guys do on those girls' nights? Can I come to the next one?"

Bernadette clocked him on the head, while Sheldon continued his point, unabated.

"Raj, however, has sexual arousal for any female who kisses him. Therefore, I will not permit you to kiss him, Amy."

"Well, you know what?" Amy said, her tone sounding incredibly antagonistic. "It's my birthday, and I can kiss whoever the hell I want."

"Yeah, that's right. You tell him, Ames," Penny cheered.

"C'mere, Rajesh," Amy said, full of vigor.

The next thing Sheldon knew, Amy was propping herself on her knees and crawling toward Raj, who sat perfectly still, although his pupils were more dilated than ever. Once Amy reached him, she closed her eyes and clumsily leaned forward. Her mouth pressed against his, hard, catching Raj off-guard at first. After a moment, though, the apparent shock wore off as he closed his own eyes and brought up a hand to cradle the back of Amy's head.

Sheldon felt his face boil. Rage. That's what this is. Definitely rage. Dear Lord, make it stop.

Amy finally pulled away from him, a grin sliding over her face. Raj looked momentarily disoriented, until he slowly cracked a small smile.

"Okay, that was pretty sexy," he admitted.

"I agree," Amy said with a nod as Raj released her. She backed away and took her place in the circle, lightly touching the corner of her mouth.

Everyone was entirely quiet. Sheldon wished now more than ever that he'd perfected time travel so he could go back in time and make it so that this party never happened. This was the absolute worst moment of his life.

Is this my punishment for not being a more caring boyfriend?

"Oh, right, it's my turn to spin," Amy said, grabbing the bottle and spinning it. "Maybe this time it'll land on you, Leonard." She bumped her shoulder against him, and his eyes widened.

"Oh-hh, yeah, wouldn't that be…something," Leonard said shakily.

It would be equivalent to an apocalypse is what it would be. I need to get out of here right now.

Suddenly, everyone was staring at him.

Can they hear my thoughts? No, that's impossible. I'm not thinking rationally. I need to…to…

His eyes traveled down, and his heart nearly stopped beating altogether.

The bottle was pointing at him.