"You're being a child." Casey huffed at him, arms crossing over her chest. Derek leaned to the right a little to peer around her so he could stare at the TV instead. He wanted to laugh because for when she gives the silent treatment it's perfectly normal but when he does it, he's being a child. "Derek," she groaned out doing things to his heart and body that no woman should be able to do.

When she stepped in his line of sight again his eyes snapped to hers where she was staring at him looking irritable, "Y'know, Case, you make a better window than a door." She scrunched up her nose and then took a breath, presumably to yell at him some more, but he interrupted, "Don't you have a date to get ready for?" He snapped and her eyes widened.

"Is that why you're mad at me?"

Derek tossed his hands in the air, nearly letting go of the remote, Super-Keener-Casey finally uses her brain."

Or so he thinks because then her brows are wrinkled in confusion and she asks, "Did we have plans tonight?" and Derek slumps down on the couch.

"I've said it before and I'll say it again; for someone so smart, you're pretty dumb."

"Well, then spell it out for me but stop sulking around the apartment and ignoring me." She sat next to him and he could smell her shampoo. Stupid girls.

"Do you like this guy?" He asked, instead, watching her intently.

Casey just shrugged one shoulder, "He seems nice, I don't know him very well…"

"You would want 'nice'." He muttered. Nice was always her type but then they never lasted because she didn't need nice.

"Well, is that so wrong to want someone nice after what I went through last year?" She snapped back and he cringed a little. Fair enough, she had come a long way since the last summer, but how could the woman be so blind. "I am not blind," she said irritably.

He hadn't meant to say it out loud, but whatever. "Blind." He enunciated heavily on the D. Casey just let out a frustrated grunt and threw her hands in the air.

"I don't know what you want from me, Derek."

"You." He opted for the truth which was, apparently, not what Casey had been expecting.

"What did you say?"

He turned to face his step-sister fully, "I want you."

She stared back at him, disbelief coloring her face. It wasn't disgust, he realized with a jolt, but she didn't believe him. "Lamest prank ever." She said.

"Casey," he tried.

"No, if you don't want to tell me what you're pissed about, fine, but you don't have to be so…" she gesticulated wildly at him, "ugh!" And then before he knew it she had disappeared into her room. Maybe he hadn't been entirely crazy to think that she might actually be into him, too, because she hadn't been disturbed or disgusted… she just, hadn't believed him. He was fairly certain, too, that had been hurt that had flashed across her face, too.

She still ended up going on her dumb date but she was home after about an hour and before he could even ask what she was doing home so early she'd breezed past him, "I don't want to talk about it," and vanished into her room again.

When she reemerged five minutes later and plopped down beside him on the couch she muttered, "He was boring… don't laugh, it's not funny." He hadn't meant to laugh, but she kind of deserved it.

"That's what you get for dating 'nice' guys, Case."

"So, what, I should be looking for the bad-boy player so I can get dumped in a few months but at least I got to have some fun."

"You never used to be this sarcastic."

"You've rubbed off on me." She grunted.

He reached over and messed up her hair, "Happy to help."

"Derek!" but he thought he saw a hint of a smile on her face. "So, you're not mad at me anymore?"

"Nah, not at the moment."

"Good."

"Excuse me, Derek." Casey said sweetly, suddenly at his elbow. He looked away from the redhead that was currently trying to keep his attention and looked at Casey.

"Can I help you?" He was testing his theory, waiting to see if he could figure out if Casey was jealous before he tried confessing his (gag) feelings again. "I'm a little busy here," he motioned to the redhead who, turns out, has an annoyingly high giggle. He watched as an imitation of his smirk ghosted across Casey's features.

"Yes, extremely busy." She deadpanned and turned to the redhead, "Hi, I'm Casey." she stuck her hand out and shook the, now confused, girl's hand.

"Amber," she introduced herself looking between Casey and himself.

"This is Derek, I'm sure you've met. He'll flirt with you for a week, two if he's feeling generous, and then he'll lose interest so let me save you two weeks and some heartbreak and recommend you find someone more worthwhile."

"Sorry, didn't know he had a girlfriend." The girl muttered, turning away.

"What the hell, Case."

"I'm saving you from yourself, Derek. That girl was vapid and I've been in class with her before, so have you I might add, and she's not the brightest bulb in the box." He opened his mouth and she held up a finger "What happened to wanting a challenge?"

He frowned at Case and instead asked, "Are you coming to practice tonight?"

She beamed, "Of course." Because she hadn't missed a practice except for that week last semester when she'd been sick with the flu.

"... so self-centered, inconsiderate," Casey was glaring at him and they were toe to toe, circling each other in their living room.

"Hey, Pot." She snarked back and she looked visibly affronted.

"I am neither self-centered nor inconsiderate." She poked at his chest to make her point.

"Please, Case, if it doesn't have to do with you then you couldn't be bothered."

"That's not true. I'm always there for the team-do you think I don't have better things to do then to bake them snacks? Because I do, but they enjoy it and I like doing nice things for them. Then there's you,"

"Me?"

"Yes, you. I help you out all the time?"

"Why?" He snapped, pushing her.

"Because I love you, you idiot!" She yelled back. Then she realized what she had said and her eyes grew wide. "Fuckfuckfuckfuckfuck." She muttered under her breath and Derek stood there, grinning. "I mean, you know like in the way that I love Edwin… or George… or… look, don't be weird about it okay? It's just a word, they're just feelings. They don't have to mean anything. I'm just… gonna… fuckfuck…"

He cut her off, "Casey?"

"Hmm?" She cocked her head at him, innocently.

"Shut up." And then he closed the distance between them, sliding his hand behind her head and firmly guiding her to his lips. His other hand snaked around her waist and he felt her arms wrap around him.

When they broke apart she was panting a little, "Derek… we can't…"

"Shut up," he said again, and leaned in for another kiss. "I love you, too." He murmured in her ear when they'd separated again, a moment later.

"Oh." She whispered, weakly.

She was his challenge and he was hers, they go together like fire and gasoline but instead of imploding they make something beautiful; he had to sit through a lot of boyfriends to get to this moment where he could kiss her and they had both grown to a point where they knew each other well enough that they could last.

"I've loved you for a long time," She admitted one evening, snuggling against him on the couch.

"Then why date all those idiots when this idiot was here all along. I thought I made it clear what I wanted."

"You did… sort of, I thought I knew, but didn't want to assume… beside, I needed to put the pieces back together, Derek. I felt broken and used and… I just needed to feel whole. And I realized, even if I wasn't completely put back together, you were still there helping pick up the pieces of myself I'd lost along the way so it was just a matter of getting to the point where I felt whole enough to be me and independent before I could even entertain the idea of an us. If we'd gotten together any sooner, I don't think… I don't know how it would have been."

In a rare moment of seriousness he leaned over and kissed the top of her head, "I'll always help pick up the pieces," he promised.

"I love you."

"I love you, too." He paused, "But I'm still not sleeping with you."

Suddenly he was being accosted by one of the couch pillows as Casey beat him with it and he laughed, "Derek!" It was music to his ears.

Fin.

A/N: So, it's not the greatest ending but I've never really been good with endings anyway. So, uh. Hope you enjoyed. 3