A/N: The italics indicate a flashback. Thanks for all the reviews! You guys rock.

Chapter 10

Derek

"Ok, so what's this all about?" Derek asked Casey. It was two weeks since the first time that they'd kissed, and despite his initial hesitations about the whole thing, Derek had found himself having more than one not-so-innocent rendezvous with Casey during the last two weeks. He had tried to fight his desire for her—he'd even tried to hold onto his remaining shred of decency that she deserved better. But after only a day of avoiding her it had all backfired once he'd gone downstairs for a midnight snack and found her in the kitchen….

….Derek headed toward the fridge, having rushed through his dinner without getting seconds so that he could rush back to his room and avoid seeing Casey for longer than necessary. As he rifled through the contents of the fridge, he heard a rustling sound behind him and looked up; it was Casey.

"Oh, sorry," she muttered, turning away.

"Wait," he called, straightening. "What were you—that is, do you want to join me?" He held up a carton of chocolate ice cream. "Your favorite flavor!" he taunted.

She smiled. "Sure. It's the least I can do after all your help with that Truman fiasco."

Derek made a face as he opened the ice cream carton. "Glad to be of service, I must say. What a douche bag."

"Couldn't agree more." Casey dipped a spoon into the ice cream and took a bite. The spoon slid into her mouth slowly, and she savored the rich taste of the ice cream. She looked up at him, raising an eyebrow. "What?" she demanded.

Derek blinked, realizing that he'd been staring at her. "Uh, you've, uh, got chocolate on your chin." It was a lie, but whatever.

"Oh, do I?" she asked, frowning and wiping at the invisible chocolate on her skin. "Is it gone?"

Derek repressed a smirk. This was almost too easy. "Hm, no, still there. Here, let me get it." And before she could protest, he leaned towards her across the kitchen island and kissed her. Her mouth was an odd mixture of cold and hot, tasting deliciously of chocolate. She gave a soft groan and started kissing him back. Her hands traveled to his hair and tangled in it, sending shivers down his spine. Derek hoisted her onto the island counter, his arms wrapping firmly around her waist, her back, her thighs, everywhere. Suddenly, something clanked onto the floor and they froze; one of the spoons had fallen to the floor.

"Uh," Derek said, pulling away a little bit. "We really—"

"—need to continue," Casey gasped, before grabbing him and pulling him close again….

So it had gone for the last two weeks: a chance encounter in the bathroom, a scheduled meeting in his room after dark, a playful exchange in the hallway closet. Derek had lost count after the first week had gone by. But when they were almost discovered by Marti though (they'd been making out in Casey's room after dinner and she'd wanted to have story time), Casey had asserted him that they had to "have a chat," and so he'd grudgingly agreed to do so. So now they were in their living room; Derek on his recliner and Casey stretched out across the couch. They'd waited until everyone else was out together seeing another family-friendly movie, and then commenced the meeting.

"We need a plan," Casey affirmed, holding up a pencil and a blank sheet of paper.

Derek raised his eyebrows. "A plan? Regarding what?"

"Us," she replied, examining the paper and scribbling something down. "I really appreciate all your help with Truman, but I don't think that what we've been doing is going to work if we keep this up. What if someone in the family notices?"

"So we just make-out until we hear the front door slam, and then we stop and pretend that we were fighting," Derek suggested, confused at why it had to be so complicated. He leaned towards her. "Plan's done. Let's test it out."

"Not so fast," she snapped, holding her hand up to block his approach. "The plan is not done. We need to discuss some rules."

"Are you kidding me? Because this is a really sick joke!" Derek flopped back onto his recliner, staring at the ceiling in disbelief.

"I'm not saying that we should, er, stop doing what we've been doing," Casey told him, her face red. "But I think we need some boundaries so that we ensure that no one discovers us."

"I don't know what was wrong with my idea," Derek grumbled to himself, but he sighed and sat up, preparing himself for an evening of very boring, very detailed planning.

Casey

Casey set down her fork and dabbed her face with her napkin. It was the next day, and she was feeling very pleased with herself. She and Derek had planned out a list of times and places that they absolutely could not… meet… together. They'd even had a little time to spare at the end….

"Ok, so after dinner is off-limits," Derek repeated, nodding. "Can we test it out now?"

"Almost," Casey told him, setting down her paper with a satisfied smile. "Repeat all the locations that are acceptable. I want to make sure you know them."

Derek groaned. "God, why are you such a keener? We're not even in school."

"Fine, then, I'll see you later," she huffed, getting up.

"Ok, ok. The bathroom, our bedroom, and the kitchen."

"Sometimes in the kitchen. Obviously if someone is there, or home at all really, then it's strictly off limits, seeing as how—"

She was interrupted by Derek's mouth. But for once, she didn't mind. It was hard to remember why she was annoyed when his hands played with her hair and his body pressed close to her own.

"How was dinner, sweetie?" her mom's voice asked, pulling Casey out of the memory. She jumped.

"It was delicious!" she exclaimed. Despite the fact that it was a Monday, she'd been in a decent mood all day: Truman had stopped pestering her after getting a beating from both her and Derek. Best of all, though, was that her plan with Derek had been going pretty well. So Casey was feeling quite proud of herself.

Nora grinned, "Well, I know you don't normally like burgers, but after Derek's winning streak I figured that he deserved a treat." She turned to Derek. "What's this, your second winning goal in just two weeks?"

"Yep," Derek said, taking a huge bite out of his third burger. Casey glared at him. He raised his eyebrows at her, smirking. "Hey, you know, Case," he said as he chewed, "normal people eat their burgers without a fork."

Rolling her eyes, she replied, "Well, cultured people typically wait to speak until they've swallowed their food."

"Mmhm," Derek shrugged, "Looks like you're the freak and I'm a typical guy then." He shoved the rest of the hamburger in his mouth and grinned at her.

Casey made a noise of disgust and threw her napkin on the table, asking, "May I please be excused?"

"Sure, honey," Nora said, shooting Derek a look. He grinned sheepishly and continued chewing.

Casey headed up to her room, selecting a book and laying on her back. She'd already done all of her homework before dinner, so it was the perfect time for a little pleasure reading.

She'd gotten several pages in when her door burst open and her stepbrother waltzed in, shutting the door behind him. Casey gulped, willing her suddenly rapid pulse to slow down.

"Hey, Spacey." Derek came over and flopped onto the bed next to her. "Whatcha reading?"

"Excuse me?" Casey wondered, furrowing her brow in confusion and inching away from him. "Don't you have a pigsty to roll around in or something?"

"Hmmm, no, I figured I'd do that in here. It's unnaturally clean, after all."

"So you've come to spread your disgusting habits to my room, then?"

"Hey, hey, be fair, Case. I brushed my teeth." He winked at her.

Casey rolled her eyes. "Ok, Derek, why are you in here?" She paused, glancing around as if someone might be in the room with them, before hissing, "You know that after dinner is a forbidden time! What do you want?"

"That's a tough one," he paused to consider for a moment. "But I'd have to say… you."

Casey sucked in her breath, feeling her eyes widen and her limbs stiffen as she comprehended his words. Slowly her eyes met Derek's; he was smirking at her, his head propped up on his elbow. "But… the plan…" she breathed at last.

"I tried sticking to it," Derek sighed, leaning back and rubbing his temple with his palms. "But then when you walked out of the shower this morning, it nearly killed me."

"Derek! Manners, please!"

He turned an innocent look on her. "What? Can I help it that you're hot?"

She hit him with her book.

"Ow!" he cried, rubbing his head. "Hey, I meant that as a compliment!"

"I know, doofus. But I thought we'd—we'd agreed to hold off on…on… doing anything until the specified times. Can't you wait until 10:30 tonight?"

"No," Derek grumbled, pouting. "I want to have fun now." He leaned over and pressed his lips to her ear, tickling her with his breath.

Casey bit back a chuckle. "So do I." She shook herself, and got back on track. "But we have to be careful. Remember when Marti almost saw us? We have to be careful about—about—this!" She gestured between the two of them, pushing him away and sticking her nose back in the book, pretending to read.

"What about 'this'?" Derek asked, tugging a lock of her hair. She swatted his hand away. "What now?" he groaned. "I'm not even allowed to touch you?"

"No. We've got to remain professional until the appointed time." Derek raised his brows, staring at her, and she swallowed, feeling uncomfortable.

After a moment, he rolled his eyes. "Come on, Case, you know you're attracted for my complete and utter manliness. You won't be able to resist for long."

Snorting, Casey gave a short laugh. "In your fantasies, maybe."

"I seem to recall that they were your fantasies, actually."

Setting her book aside, Casey pursed her lips in annoyance, narrowing her eyes. "And I seem to recall punching you when you kept bringing that up. Do you want me to do it again?"

"Well, if you're into that sort of thing. I'd be willing to experiment."

Casey huffed and whacked Derek with her pillow. "You're impossible, Derek Venturi."

"Thanks." He laughed, swatting her right back with the other pillow. "It's a compliment I get a lot."

They continued to rough-house with the pillows for a few moments, laughing all the while. Derek grabbed the pillow from her, holding it away from her. She leaned across him on the bed, reaching for them. He smiled up into her face, propping himself up on his elbow and pressing his mouth to her own. She gave a little gasp at the sudden contact, her eyes fluttering closed as she felt his mouth open under hers.

The pillow fight was forgotten as they continued. Casey's heart pounded in her ears as she cupped his face in her hands, tasting him with her tongue and shivering as his hands slid under her shirt, caressing the bare skin of her back, before starting to tug her shirt off. Casey paused, trying to concentrate enough to decide whether or not they should continue. He'd locked the door… but someone might knock and become suspicious as to why they were both barred in her room together. But then Derek's hands started roving over areas that they hadn't yet explored, and Casey forgot to think.

"Casey," he whispered against her lips, and she pulled his shirt off. Her hands gripped the lean muscles on his back, her fingers digging into his skin as Derek's mouth went to her neck, her chest, her stomach in a trail of kisses….

A distant door slam startled them as his hands brushed against her panties line. Casey groaned in annoyance at the sudden pounding in her chest from her nerves over being discovered.

"What the hell was that?" Derek said through gritted teeth.

"There are other people in this house," Casey grumbled, equally annoyed. "Unfortunately."

Derek was grim for a second, before glancing back down at her and smirking. "Wanna finish this later?" he asked, wiggling his eyebrows.

"Sounds good," she replied, her voice coming out huskier than she meant it to, and Derek groaned. "10:30 ok? My room?"

"If you want me to survive that long, you can't talk like that," he said.

"Sorry," Casey replied, clearing her voice. "I can't help it, either, you know."

"I know, I know," he reached down and brushed a stray strand of hair from her face. "You're beautiful," he whispered suddenly.

Casey felt her face grow red. "I'm sure you say this to all your girlfriends." It was a topic of insecurity that they still hadn't addressed.

Derek was silent a moment, the ghost of a smile still on his lips. "When I kissed those other girls, I never meant it." He brushed a kiss onto her forehead. "No other girl makes me want to pummel her ex-boyfriend." A dark glare flitted across his eyes, then faded as he turned his gaze upon her again. "No other girl makes me unsure if I want to kiss her, scream at her, or tease her." Casey felt a smile start on her face. "And no other girl has gotten under my skin like you have, so that I find myself surprisingly enjoying it."

"You're—you're just saying that," she whispered, although she was starting to believe him.

Derek laughed softly and chucked her chin. "No way, McDonald." He held up his hand, and she saw with some surprise that it was shaking. "See what you've done to me?"

The smile bloomed on her face, and she reached up to kiss him passionately. When they pulled away, he was smiling down at her, his eyes crinkling with affection. "To hell with the plan," she cried. "I'm not waiting until 10:30."

He raised his eyebrows. "Wait, hold it!" He put on a face of disbelief. "Did Casey McDonald just blow off one of her own plans for her obnoxious stepbrother?"

Her grin widened. "I learned from the best," she whispered, before pulling his lips back to her own.

THE END.

A/N: I hope you all enjoyed this story! I'm going to miss it. I might add a little epilogue as a treat for all of you lovely readers. ;)

Anyway, I had a great time writing this fic, and I loved each and every one of your reviews. I really do appreciate the feedback. Thanks guys! *hugs all around*