AN: Yay! I wrote a fic! For Rose (TheBlueCrystalRose), thank you so much for everything!
For the record, I know absolutely nothing about Grand Theft Auto so I'm really sorry if that part doesn't name sense.

Disclaimer: I do not own Life With Derek or Grand Theft Auto or Barbies.

"Why me? Why me?!" thought Casey McDonald as she lay in bed, staring at the ceiling.

"Why did I blush? Why did I run? What is wrong with me?!"

Casey sighed. Earlier that day, she had come out of her bedroom only to be met be one Derek Venturi, dressed in just a towel. If that weren't enough, there had been beads of water dripping down his toned chest, accentuating his muscles. Now, Casey had seen Derek in just a towel before, but this time she had felt this strange sensation in her stomach; almost like… butterflies. She had felt the blush creeping up her cheeks, and before she knew what she was doing, she had turned and run to her room.

There she was now, and after making two lists, three charts, and six graphs, she still could not comprehend what on Earth had happened to her.

"I gaped at him. Gaped. At him! Casey McDonald does not gape. Much less at him!"

Convinced she would never figure it out, she pushed all thoughts of Derek aside and concentrated on falling asleep.

"Don't think of Derek. Don't think of Derek. Think of… puppies! Puppies. Puppies are nice. They're so cute! Especially ones with brown fur. Brown fur is really nice. So is brown hair. Derek has brown hair! It looks cutest in the morning. Right after he gets out of bed and it is kind of messy, but in a really cute way… Wait, what? No! I did not just call Derek cute! I didn't! I…"

Casey sighed. Since she obviously wasn't going to be able to fall asleep now, she might as well put this spare time to good use.

"I guess the kitchen could use a good cleaning…" sighed Casey as she trudged downstairs. But there on the couch sat the one person she desperately needed to avoid. Maybe he didn't see her! Maybe she could sneak back up the stairs before he-

"Hey, Space Case. Finished next year's homework yet?"

No! She couldn't go now, he had seen her already!

"Umm, uh…" Casey stuttered, at a loss for words. She tried to come up with something intelligible to say, but nothing came to her.

"Well, I um, sort of, uh… What are you playing?"

Wow. Real smooth, Casey. Because that's exactly what you want to be doing; giving him a reason to say something to you!

"Grand Theft Auto."

"Why?" asked Casey. "That game is stupid."

"It is not!" replied Derek. "It is a manly game, unlike those stupid girly games you play. I mean, come on, Case. Barbie Fairytopia?"

"That is Marti's! I do not play with anything to do with Barbies. They are totally unrealistic icons of women created just to make girls feel bad about themselves! I would never play with something like that."

"Maybe," Derek answered, "but that still doesn't mean you can play Grand Theft Auto."

"I could too! In fact, I bet I could beat you at Grand Theft Auto any day of the week!"

Derek smirked. There was no way his prissy, pouty, Klutzilla step-sister could beat him. But, then again, it would be kind of fun to see her fail.

"You could never beat me. I mean, I'm me, and you're… you! You've never even played it before; you wouldn't know what to do."

"You could teach me."

This caught Derek by surprise. He wasn't expecting that kind of reaction from her, how was he supposed to respond?

"Umm, okay, I guess…" Derek motioned for Casey to sit down on the couch next to him.

"Well, you have to reach a target number of points, which you do by performing crimes. Each level has a different set of crimes. If you successfully complete the crime, you get points and more crime opportunities. But if you fail, you might not get the opportunity to do other crimes. Now, you see this button here? This is for…"

As Derek explained the game to Casey, she watched him intently. Had his eyes always been that brown?

"…to complete the task. You got it?"

Casey suddenly snapped back into reality. What did he say?

"Umm, yeah, sure. Okay."

As Casey first started off, she wasn't very good. But after a couple tries, she began to get the hang of it. Derek was surprised, she wasn't half bad. Actually, she was kind of… good! Derek watched her as she played. The way she scrunched her eyebrows together and the way she slightly stuck her tongue out when she was frustrated was kind of…

"No Derek. She's your step-sister. She's practically your sister! Get a hold of yourself. She's not… cute" thought Derek.

But the way her eyes sparkled when she completed a task, and the way she smiled at him when she beat the level had Derek thinking about changing his mind about that.

An hour later they were both so tired they could barely keep their eyes open. They turned off the game and Casey sat looking expectantly at Derek.

"What?" he asked.

"Well? Who won?"

"Ummm… I don't know" Derek replied. "We'll have to play again tomorrow night." Was Derek imagining things, or was there a hint of a smile on Casey's face?

Casey noticed him staring at her and quickly covered her smile with a frown.

"Well, okay, if we have to."

As they were putting the controllers away, Casey tripped over a cord and hit her head on the corner of the coffee table. As she fell she threw the controller up in the air, and it landed on her head, right where she had hit it. Casey yelped in pain, and a large bruise could already be seen forming on her forehead.

Upstairs, George had heard the scream and wondered what all the commotion was. He sleepily came downstairs to find Casey lying on the floor with Derek standing next to her, looking unsure of what to do.

"Casey! Derek! What on earth are you two still doing up; it is past one in the morning! And Derek, don't just stand there, get your sister an ice pack!"

"Step-sister" Derek corrected his dad. "And can't she just go and stick her head in the freezer or something?" he called after George, who had already begun walking back upstairs.

"Der-ek!" Casey cried in frustration. It was then that Derek knew Casey was okay.

"Derek, I could have a concussion! A brain hemorrhage! I could be internally bleeding to death right now, and all you can say is-"

"Okay! Okay! I'm going!" Derek cut her off.

He returned a minute later with a cold ice pack in hand and some green Jell-o. "Here you go, Ice Princess. Okay, now you should lie on the couch and, um, elevate your leg, and the Jell-O should calm your stomach and keep you from throwing up…" Derek put the Jell-o on the table and helped Casey on to the couch as he placed the ice pack on her head and took a seat next to her.

"I hurt my head, not my foot, and I don't have the flu, smarty-pants! If you didn't know that it's a wonder how you passed elementary school!"

"Well, excuse me for trying to help my sister when she's hurt!" Derek turned to leave.

"Step-sister." Casey's reply was so quiet he could barely hear it.

Derek turned his head to look at Casey. Had her eyes always been so blue? As Derek looked into her eyes, Casey could no longer feel the throbbing pain in her head, and they were both totally unaware of anything but each other.

There were a few strands of hair falling just beside Casey's left eye. Derek inadvertently pushed them away. It was then that Casey became aware of the very few centimeters between them and as her lips began to tingle, she wondered what it would be like to have Derek's lips against her own.

As Derek and Casey inched their way towards each other, never breaking eye contact, their heart rates began to speed up. They were thinking of nothing but each other. Suddenly, Derek's hand went up to Casey's ice pack, keeping it from falling, and Casey's eyes fluttered closed. Derek took this as a sign, and closed the gap in-between them.

The feeling of Derek's lips on hers was like nothing Casey had ever felt before. It was the best feeling in to world. Their lips lingered there, memorizing each others' touch. Electricity sparked between them, it was if fireworks were going off. It was passionate, but innocent. It was soft, but sweet. It was perfect.

After they reluctantly pulled away, Derek looked into Casey's eyes and smiled.

"By the way, you totally won Grand Theft Auto."

Casey smiled back and they resumed their new favourite activity.

After about a minute more of kissing, Derek pulled away again, this time sporting that adorable smirk that made Casey's heart skip a beat.

"Also, I put honey in your shampoo." Derek said before running away laughing.

Casey's jaw dropped. "Der-ek!" she cried. She chased after him, smiling the whole time.

So, maybe they weren't the most conventional pair…

They were perfect.

I hope you enjoyed!! Feedback is greatly appreciated. Thanks!!!!