A/N: Wow. I didn't know I'd get such a positive response – and from just one chapter, too! I had a little bit of a block when writing this chapter. I wasn't quite sure how to set up the boundaries of 'The Bet,' but then I figured it would be more fun to express these boundaries as the story goes on. Please, continue to let me know what you think.

Thank you for all the reviews! You guys are too kind.

No, I don't own. Although whenever I watch the show I fangirl squee and wish I could have a Michael Seater. swoons

Best Imitation of You

Pairing: Dasey – Derek/Casey

Summary: "I'll bet that you can't be like me as well as I can be like you." Derek and Casey make a bet in the hopes of teaching the other a lesson. They end up learning some other things in the process.

--

Chapter Two – Rules and Regulations

After a long week filled with classes and work and soccer drills, Lizzie McDonald was looking forward to taking the weekend and unwinding. Her stepbrother, Edwin, seconded that motion, having every intention of trying out that new face cream he was working on since he didn't know how long that certain color of mold would last.

The one thing Lizzie and Edwin did not foresee was a calm and waiting Casey and Derek. As the two siblings threw open the door with mutual sighs of relief, Lizzie glanced over at the living room couch to see Casey and Derek sitting and watching her and Edwin's every move.

Something was going on. Something big.

"Lizzie? Edwin? Come here for a second please."

The polite tone in Casey's voice didn't sound menacing or formidable. Maybe she hadn't figured out her favorite headband was currently missing and in fact buried beneath soccer pads in Lizzie's gym bag. Edwin was a little more hesitant, eyes bulging as he watched Lizzie walk over to face the siblings.

There was a certain smirk on Derek's face. A smirk that told Edwin that he was about to be told to do something that may or may not be fun. A quick mental calculation said 87 percent of the time it wasn't fun.

"Edwin. Come on."

Inching slowly towards Lizzie and the couch, Edwin quickly began filtering through his past experiences with Derek to determine what in the world was going to be asked of him. Luckily, he didn't get thinking far past the time that involved make-up and one of Casey's forgotten skirts (which had been horrifically traumatic for a boy of thirteen) before the two older siblings laid out their request. Literally, laid it out onto the coffee table.

Two pieces of paper were placed in front of Lizzie and Edwin, respectively. Casey and Derek wore matching grins, adding even more to the disturbing vibes that the situation held.

"Edwin, Lizzie, we, Casey and I, are trusting you to be the anchors in our latest scheme."

"Competition, he means. No scheming." Casey turned to Derek and scowled before facing Lizzie and Edwin again, returning to her professional face. "What we mean is, we've made a bet and we want you two to supervise it to ensure there is no cheating," she shot a glare in Derek's direction, "or any other funny business."

Making a mocking face at the words 'funny business,' Derek held a hand up to Casey's face briefly and turned his attention to Edwin and Lizzie. "In other words, you're gonna help write out our rules and whatnot."

"And you're going to chart our daily progress. And at the end of a week, you will determine the winner."



Lizzie picked up one of the papers and read the heading. "'Casey and Derek's Rules and Regulations to Ensure that The Bet is Followed Out in a Just and Honorly Manner'? Catchy title, really."

"So," Edwin started, breathing a short sigh of relief – he was not to don a dress or one drop of eye shadow, this was good – before launching into his business persona. "What is 'The Bet' and what are the conditions?"

--

After everything was written out in an organized manner, Edwin and Lizzie reviewed the contracts. "Let me get one thing straight," Edwin began, taking a moment to look over Rule Number 7: No receiving helps/hints from other parties. "Neither of you are allowed to go to any person, including best friends, exes, parents, and teachers. But what about us?"

"He's right. You guys come to us all the time, especially when it concerns getting back at each other."

Derek and Casey thought for a moment. "Well," Casey said, looking at Derek for a reaction. "I think they should be an exception. They are judges, but who's to say they can't also be coaches? I trust them to make an unbiased choice when the final decision must be made. Derek?"

Holding his chin with one hand, Derek glanced up at Edwin and then at Lizzie. "I agree. But, instead of me and Edwin and you and Lizzie, I think it would be only fair for me to have Lizzie and for you to have Edwin." Before Casey could object, Derek continued. "Because, Edwin knows me more than Lizzie does, just as Lizzie you more than Edwin."

Taking this idea into consideration, Casey stole her own glances at Lizzie and Edwin. "As much as I hate to say this, you've got a point Derek. I'll take Edwin as my coach and you can take Lizzie."

"Now that you two are done bartering over who gets which one of us – which really makes me feel more like a human than some common cattle, thanks guys – can we decide on a start date?" Edwin waggled a pen over the paper he held in his hand. "The agreed time period is a week, so when shall it start and when should it end?"

"Well, since I have a date on Saturday night, I think it would be only practical to begin after the weekend." Derek smirked and turned to Casey. "What about you, Spacey? Got any super important plans this weekend? Ones where it's crucial to be your own special self?"

Rolling her eyes, Casey crossed her arms. "Unlike you Derek, I don't have any plans to take advantage of the entire female population before I turn twenty, nonetheless this weekend."

"Oh, but you will over our seven day bet period. Remember, my life philosophy includes testing the waters with every member of the opposite sex I can. I am, first and foremost, a ladies' man at heart."

Lizzie began to laugh. "That's right! Casey's gonna have to pull off being a female player. This is going to be so – " Lizzie paused, a glare from Casey making her rethink her choice of words. "Interesting. So interesting."

"I think Casey can do it," Edwin stepped in, receiving a look of shock from all three of his siblings. "I mean, Casey's appealing, in a, you know, female kind of way and…stuff." He stopped to ponder the 'stuff' before shaking his head and continuing. "She's just got to have the Derek attitude and method. And I know enough of how Derek operates to help her bag as many guys as she can."

"Coming from the boy who has yet to snag a date with a girl."

"Hey! There was that one time with Ashley, when she invited me over to her house."

"That was her birthday party," Lizzie sighed. "She invited six other guys, as well as ten girls."

Casey came to Edwin's aid. "Thank you Edwin. I appreciate your enthusiasm. I know that with you I stand an even better chance at defeating Derek at being, well, Derek." Casey and Derek exchanged hostile looks that bristled with tension.



Lizzie shook her head and turned to Edwin. What had they gotten themselves into now?

--

Just as Edwin was about to climb up to his attic room and start his Friday night relax routine, he was jerked by the arm into the unlit game closet.

"Ow! Derek! What's your deal? Jeeze."

Derek held a finger to his lips. "Shhh, Edwin. Make some more noise, why don't you?"

Edwin groaned as he rubbed his arm. "What do you want, Derek?"

"I want to make sure you know where your loyalties lie."

Blinking in the darkness at his brother, Edwin realized how tall he was getting. And, in consequence, how much shorter Derek seemed. "What do you mean?"

"I mean, you are going to help sabotage Casey's efforts to ensure that I win, right?"

Edwin raised an eyebrow, although he knew Derek probably couldn't see it too well in the dark. "What makes you think that?"

Chuckling lightly, Derek grabbed the front of Edwin's shirt. "Because I know how much you enjoy the feel of air passing down into your lungs."

"And what if I decide that being true to the contract is more important than that?"

"Then I'd say I have traitor for a brother."

"And then I'd say that Derek's a dirty cheater."

The door swung open, light from the hallway nearly blinding the Venturi boys. Casey stood in the doorway, hands on her hips. "Derek, let go of Edwin. It's only a few hours into our agreement and you're already trying to find loopholes and ways to manipulate your way to victory."

Releasing his hold on Edwin's shirt, Derek held his hands up in the air. "Well, you know me, Case. I'll go to any means to achieve my goal. I've got to see what I get now before Monday comes and I have to start acting like you. And heaven knows you never try to cheat. Or grade grub. Or anything else to gain an upper hand. What. A. Saint."

He pushed past Casey as he left the closet, his shoulder shoving into her shoulder and almost knocking her off her balance. Casey scowled as she shuffled her feet and regained control of her stance. Turning to Edwin, Casey grabbed the front of his shirt and pulled him towards her room.

"Hey!"

"C'mon Edwin. We've got work to do!"

Edwin exhaled loudly, wishing his siblings would stop this nonsense. He really liked this shirt and would prefer if it would stop getting so stretched out.

--

After a few hours of catching up on the worldly events (why can't people just ride bikes everywhere? It'd save the environment and money) and the latest on Instant Star (Jude and Tommy are just too cute together), Lizzie made her way upstairs. There was a pillow with her name on it, and she planned on getting real comfy with it.

Too bad she felt a yank on her hand as she walked past the bathroom.



Casey beckoned her into the bathroom, closing the door behind them. Taking the toothbrush out of her mouth, Casey directed Lizzie to sit on the toilet as she settled onto the edge of the bathtub. Before Casey could start, Lizzie held up one hand.

"I hope you didn't bring me in here to ask me to spy on Derek's tactics. Because that wouldn't be fair, seeing as you busted Derek for trying to do the same thing with Edwin only a few hours ago."

Casey frowned. "That's different! Derek is just trying to get both you and Edwin on his side. I just want to make sure that you remember all the nice things I've done for you all these past few years we've lived together. And the fact that I am your sister, and we share a special connection by blood. And to let you know that I know you've been eyeing a certain 80 gig Zune in tree bark brown."

"Sweet talking and bribing me doesn't work at all, Casey. I signed an agreement. On non-recyclable paper, too, by the way. You know how much of a sacrifice that was for me."

Pouting, Casey tried again, "But Lizzie – "

"No buts!" Lizzie stood up and walked to the door. Turning to look at a crestfallen Casey, Lizzie sighed. "Casey, you'll be fine. How long do you really think Derek's going to last as you? As your sister, I believe in you."

Casey smiled brightly at her sister. "Thank you, Lizzie. That means a lot to me."

"But, don't think I won't help Derek in any way I can. Well, at least in an honest and fair manner. Edwin will do the same for you." Lizzie twisted the doorknob and grinned. "May the best impersonator win."

After Lizzie left, Casey stood up and finished up with her brushing. As she bent down to spit into the sink a final time, she felt another presence slide up next to her.

"Only a few hours since our agreement, and you're already trying to find loopholes and ways to manipulate others? Why Casey, you don't have to start being me until Monday. What's gotten into you?"

Shoving Derek aside with her hip, Casey wiped her mouth with a towel and put her toothbrush into its matching holder. "Whatever Derek. At least I wasn't using violence as leverage."

"Because buying Lizzie is so much nicer."

Turning to face Derek, Casey locked eyes with the taller boy. Their gazes connected for a few seconds, intense and uncertain. Slowly, Derek raised a pointed finger to Casey's mouth. Flinching only slightly, Casey held her ground.

What in the world is Derek doing?

"Casey?"

He moved closer, bringing their faces only a few inches apart.

"Um, Derek?"

"You've got toothpaste." Derek poked the corner of her mouth. "Right there."

After Casey hastily wiped away the last of the white residue, she stormed out of the bathroom, fuming. From her bedroom and through her closed door, she could still hear Derek's boisterous laughter.

He won't be laughing when I beat him at his own game.

--

to be continued…