A/N – Sorry for getting so late. I know I'm practically one of the worst when it comes to updating, but exam time can do that to ya..

I do not own Life With Derek.

Enjoy!

…

"This is ridiculous."

"I beg to differ. I think it's necessary."

"In what universe is this necessary?"

"A universe where you promised to do five things that I wanted you to do."

She rolled her eyes. "And you just had to pick something stupid."

His grin widened. "Why yes. I did."

Glaring at him for good measure, Casey shifted onto her other foot.

"Ah ah ah." Derek sniffed obnoxiously. "You still have..." He squinted at his wrist watch. "…forty five more seconds to go."

With a huff, she jumped back onto her left foot. "Are you counting properly?"

He gestured to his watch. "Digital. I can't go wrong."

Casey scoffed. "Obviously it's digital. It's not like you can read a proper clock with numbers."

His eyes narrowed. "Is that a snide remark I hear?"

Casey's eyes widened. "What? No. I was just making a passing comment about…"

"Next leg."

She jumped onto her right leg. "…about how you are very…" He looked at her expectantly. "…proficient… in telling time…digitally."

"Ooh. I'm sorry, but it looks like you have just insulted me again. You know what that means…"

"Derek…"

He reached for a card, his expression fully showing evil glee. "Ha! This is a good one." He flipped the card over so that she could see it. "Eight of spades." He gestured for her to move quickly.

Rolling her eyes, she jumped back onto her left leg, simply moving her hands so that the heart shape she made with her thumbs and forefingers were upside down. "This is a stupid game."

Grinning, Derek leaned back onto his forearms, as he lazily eyed her from the bed. "You were the one who wanted to pick the five random things."

Her jaw dropped. "No I didn't. I didn't want to do any of this."

"Oh, that's right. I remember something about a paper…"

"Am I done yet?" She sneered.

He shrugged. "Next leg."

With a sigh, she started balancing herself on her right leg. "I can't believe you roped me into playing this stupid-"

"Genius" He interrupted.

She glared at him. "-stupid game. This is the worst card game. Ever!"

"I don't know." Derek's tone had a hint of mock thoughtfulness. "You insult perfect little ol' me, which leads me to pick a card, and then you get to be the poster gal for that card." His grin widened. "I think it's pretty inventive."

"Making me balance on one foot for a certain number of minutes equal to that of the card is inventive?" She snorted. "You must not be used to such intelligence."

He raised his eyebrow at her. "I believe we just got another insult there."

Casey's face paled, as she shifted to her other foot. "No it wasn't."

"Let's just let the jury decide." He cocked his head to the side. "Judge Derek thinks…"

"Derek! I swear if you…"

"Casey McDonald, you are guilty of insulting this perfect specimen. As a result, you are sentenced to..." He reached for another card from the shuffled pack beside him.

Casey's eyes widened. "You wouldn't."

He pouted. "But you're guilty." With an evil leer, he picked up the next card. "You have now been served…" He flipped it over. "…with a four of clubs." He looked back at his watch. "Which will start in another three minutes."

She huffed as she changed legs again. "I hate you."

He winked. "You love me." He snuggled further into the comforter. "Now, how about singing the 'Spider Pig song' to while away the time?"

She landed on both feet for a split second in order to pick up a pen from the nearby table and toss it at his head. The fact that it harmlessly bounced off his chest instead of bludgeoning him painfully to death, didn't help matters. It also didn't help that Derek saw the attempt to end his life as an insult against his very existence and picked up another card.

Yeah, someday…she will be the puppeteer. And Derek is going to curse the day he made her stand on one leg for over half an hour.

It took promising to play the game once more before they left on Sunday, for Derek to finally let up and allow her the decency of using both legs to distribute her weight. But that doesn't mean that she's thankful for it. And the fact that it was just past midnight, didn't hurt.

"What do you think you're doing?"

Derek paused at the panic tone in her voice. "What does it look like I'm doing?"

Rolling her eyes, Casey sat up in bed. "It looks like you're taking off your t-shirt."

He scrunched up the piece of clothing and tossed it to the side. "Way to go, Einstein. You can see." He turned his attention to unzipping his jeans.

"Whoa!" In a panic, she put up her hand to stop him. "Just…whoa there!"

He let out an unenthusiastic sigh. "What now?"

"Why are you losing your pants?" He had absolutely no reason to be pants-less. He better have a good reason for what he was currently exposing her to.

He sent her his famous Derek Venturi smirk. "Because it's obvious you can't stop looking at…this." He gestured to his body.

Casey blanched. It's irrelevant how toned he was. He is not supposed to... exhibit himself. It's degrading. "Please, just try to keep me away." She rolled her eyes and added as much sarcasm as she could.

His grin didn't waver as he swiftly unbuttoned his jeans, pulled down the zip, and dropped his pants. With a slight gasp, she turned her head away. Even though, technically, she might have seen a glimpse of his black boxers. A quick flash of it, really. It wasn't anything substantial enough to imprint into her memory or anything. "What's wrong, Case? Shy?"

She scoffed, before she realized that her step-brother sounded awfully close. She turned her head, only to glare determinedly at his face, and not anywhere lower. "Aren't you changing?" Her step-brother? Currently in bed with only boxers on? Not good.

"What? You don't like these?" He looked down, moving the comforter off his lap.

She pulled at the material from his fingers and covered him up again. "I'm not sleeping in the same bed with you if you're wearing only that."

He shrugged as he started to get more comfortable. "Fine. Hope the floor's comfortable." And with that, he slid down, turned over so that his back was to her, and started fake snoring. She rolled her eyes at his incessant childish behaviour.

Honestly, where was chivalry when she needs it? "Why don't you put some pants on at least?" She tried to say it calmly, but the words were forced through gritted teeth.

He stopped snoring to mumble one word. "No."

"De-rek." She whined. She was tired, and cranky, and she wasn't in the mood to debate with her annoying step-brother while he was only in his underwear.

"Ca-sey." He mocked as he turned over to face her. "I told you. Reduce the heat, and I will gladly put pants on."

"But I'll freeze."

"But I'll be decent." He wagged his eyebrows at her.

That fact was too good to ignore. "Fine. So if I increase the A/C…"

"I will put clothes on…"

"And if I don't…?"

He grinned. "The boxers come off."

In a flash, she was off the bed and across the room, adjusting the thermostat. She faced him, smugly. "Happy now?"

Derek was already off the bed and pulling on pajama bottoms, chuckling to himself. "It's so easy to get you to do things."

"You keep thinking that." With a huff, she slid back under the covers. She couldn't help but watch Derek as he opened the closet on his side to pull out a t-shirt. Unconsciously, her eyes roamed over his slightly tanned, naked back. From the base of his neck where his hair ended, to the muscles that seemed to ripple across his shoulders and arms, to the slim, toned smooth skin of his waist. Unknowingly, she studied the lines and curves as he moved, especially the long dip in the skin along the length of his spine. She blushed as she realized that her eyes had made it to where the pajama pants hung loosely on his lower hips, and lingered there.

When Derek finally pulled on his t-shirt, and turned towards her, she was sure she was a crimson red. He looked at her questioningly, which proved her suspicions. "What?"

She snuggled further into the covers, knowing that she was nearly as bright as a red light bulb. "Nothing."

Shrugging to himself, he got under the covers next to her. "Why so far, Spacey? Scared I'll bite?"

The only response she could come up with was highly mature. She stuck her tongue out at him. He laughed lightly before he pulled her towards him by the waist. She gave in with minimal struggle.

"Don't forget, Case. You owe me." And with a perfectly charming smirk that she thinks resembles how Hitler smiled, he lied down practically on top of her, and got comfortable.

"Idiot." She reprimanded, and was slightly disappointed when her retort came out more affectionate than anything else. Her mind immediately started moving at warped speed. Her thoughts landing on several areas within a few seconds. She briefly wondered why he always slept with his hips away from her. And she also wondered if their relationship was really that bizarre. But ultimately, the last thought that crossed her mind was…at least he's warm. And with that thought in her head, she snuggled against him and slept.

When she woke up the next morning, he was gone. She immediately felt the lack of weight against her shoulder where he usually rested his head, across her waist, where he always circled his arm, and the edge of one thigh, where he normally leaned against her. While her eyes stayed closed, she tentatively moved her now free arm around the smooth cotton, expecting to bump into skin. Which didn't happen. She opened her eyes grudgingly, hating the fact that after one night, she was already too used to waking up with Derek alongside her.

She knew she hated him for a reason.

The next time she saw her step-brother, she was towelling her hair after a nice, long, warm shower.

"Missed me?" She snickered in good humour.

He smirked. "You know it." And with a grunt, he deposited his duffel bag onto the bed. Casey recognized it as the bag he took out of the closet a few hours before.

"Where was it?"

"Spencer's room." He mumbled distractedly as he unzipped the folds open, and proceeded to remove his articles of clothing. "Was planning on spending the night there."

Moving slowly, she took a seat on the bed, beside his bag. "We have one little fight, and you were prepared to spend the night with the guy you swear does black magic in his sleep?"

He paused his actions to glance up at her. Their eyes met for a few seconds before he went back to concentrating on his task. "That's what siblings do, Case. We fight, we move out. We make up, we move back in."

She couldn't help but study him. "And you would know this how? I know you have two siblings, but one worships you and the other is afraid of your disapproval."

"Four." He mumbled, as he kept his head ducked down.

"What?"

His gaze met hers seriously, and she unconsciously flinched. "I have four siblings." He continued to stare at her, and Casey couldn't help but feel like he was trying to tell her something.

"Four." She asked or confirmed. She wasn't sure. But one thing was obvious, she sounded breathless, which is completely ridiculous. Have they not always insisted on the 'step'? When did this happen?

He shrugged. "Four."

She looked away. "Oh." This conversation turned weird very quickly.

He glanced at her curiously. "What?"

It was her turn to shrug. "Nothing." She opened her mouth to ask something insignificant. Something in the lines of, whether she could go down for breakfast yet, but instead, something else came out. "I never thought you would look at me as anything more than a step-sister."

He smirked. "Don't you mean anything less?"

She slapped his shoulder with the towel, even though her lips couldn't help but twist in amusement. "Being related to you is a demotion."

He placed his hand over his heart. "I think you just hurt me there."

Grinning, she shook her head, happy that they've gone back to their bantering dynamic. She never liked it when they spoke seriously with each other. But still…

Without thinking much about the implications, she stood up swiftly and moved behind him. As soon as her arms circled his waist, and her cheek rested against the smooth roughness of his leather jacket, he froze. "Casey." She wasn't imagining it, she was sure. He sounded like he was being strangled even though her arms stayed lightly around him.

She moved her face slightly, so that she spoke against his shoulder. "What?"

He stayed silent, his hands covering hers and feebly trying to pry her off him. All he had to do was gently remove her fingers. But he didn't. "Nothing."

She smiled lightly, knowing he could feel her lips forming against him. "I'll see you downstairs."

He said nothing. Just nodded slowly.

Feeling her heart beating maddeningly fast, she untangled herself from around him. And without another word, she stepped out of the room, and closed the door behind her. The minute he was blocked from view, she grabbed onto the wall to steady herself. Her legs felt like jelly, and any minute now, she was going to end up as a pile on the floor.

Taking a few deep breaths, she calmed her racing heart forcefully, and started towards the elevator. She was in no condition to take the stairs.

As the doors closed, and she was left alone with no one around, she leaned against the steel wall and took in deep breaths. What had just happened? What did she just do? And most importantly, why did she do it?

When Derek had compared her to a sister, all she could think about was proving him wrong. She could never be his sister. She's never wanted to be. And now…what the hell is he thinking right now?

...

A/N 2 - Sorry for the short chapter, but I felt that this was an appropriate break in the story.

Also, for those who are wondering about the game Derek invented, here are the rules as per what he wants.

For every insult Casey gives him, he gets to pick a card from a shuffled deck. Depending on the card he picks, she must be a physical manifestation of that said card. And she must do this while standing on one leg, alternating every minute, for the number of minutes equal to that of the number of the card.

Eg : If Derek picks a five of spades - She has to stand on one leg for five minutes, alternating legs every minute. And, to make things even more humiliating, she must form the 'spade' sign with her hands.

Derek started the game by taking the fact that she wrote a paper about him in an unflattering light, as an insult, and then goading her into insulting him so that he could pick one card after another.

Evil, yes? *snicker*