It's an unspoken agreement that they don't bring up what happened at dinner. In fact, no one mentions it the rest of the weekend, although Derek does find Lizzie and Edwin whispering in the Game closet more often than usual.
He ignores it because they've always done their own thing, and honestly, he can't be bothered.
The car ride back to school is awkward. Casey won't look at him, or yell at him. She talks to him, so it's not the silent treatment, but he can't escape the feeling he's still being punished.
"I'd think you'd be grateful that I'm not nagging at you, anymore," Casey says when he mentions it.
"So you're doing me a favor, then."
She huffs. "I wouldn't go that far." He feels slightly accomplished at her irritation and wonders if anyone else has a… - he doesn't want to use the word friendship, a relationship certainly isn't accurate, and the idea that this might be a familial relationship makes him sick to his stomach.
It's just, he wonders if anyone else has as complicated communication issues as him and Casey. "Being home is… I don't know, it's weird. We haven't been at school that long, but it already feels so different." She shrugs, turning away from him. "I know it's silly."
"It isn't." Derek doesn't look at her as he says this. It's not something he does easily (or willingly in most cases), agreeing with Casey. In this instance, though, he gets what she's trying to say. "It is a little exhausting, isn't it."
She gives him a grateful smile (and it doesn't do a damn thing to him), and they go back to a semi-quiet drive.
…
The thing is, Derek's a damn good liar. He can manipulate the truth to his advantage. He can say the right words to get what he wants. Derek doesn't lie for pleasure, either; sure, it's fun to work the system, but it's more about getting what he wants and, sometimes, nothing good can come from the truth.
Since the McDonalds entered the Venturi residence, though, a strange thing happens when he lies. There's a little twinge in the back of his mind: guilt.
Derek didn't do guilt before a certain someone entered his life.
The more harmless the lie is, the less noticeable the twinge is, but it's there.
It's the same twinge he gets when he self-analyzes exactly how Casey's smile doesn't do strange things to his insides.
After all, lying to yourself is just a hop, skip, and a jump away from denial.
Sometimes nothing good can come from the truth.
…
It's a week later, and he's casually dating someone. He says casually, because she comes over sometimes to hang out, and they get along really well (particularly when their clothes are scattered on the floor), but he wouldn't go as far as to call her his girlfriend.
It's easy, uncomplicated.
He says dating because he spends more time with her than he has with other girls he's met at Queen's.
Casey finds out approximately one week later (he's not hiding it from her, he just hasn't… mentioned it-which is not the same as hiding). She's knocking at his door, and he's opening it wearing nothing but his jeans.
She blinks at him, cheeks turning pink. Darla comes to stand beside him, wearing nothing but his shirt, and Casey's cheeks darken further. "Gave her the shirt off your back?" Casey snarks. She continues grumbling, "Could you be any more predictable?" The look she gives him makes him feel more naked than he actually was twenty minutes ago.
Darla looks between him and Casey in surprise. "I'm sorry. I didn't know he had a girlfriend." She seems embarrassed.
Casey and Derek rush to speak over one another.
"She's not my-"
"Not in a million years-"
"-accident by marriage-"
"-not to mention so weird-"
Darla is looking between them, slightly bemused and Casey huffs. "I'm his stepsister, not his girlfriend."
Darla brightens. "Well, I have to get going, anyway." She gives Derek a kiss on the cheek and disappears back into his room to gather up her clothes. Casey says nothing, waiting on the outside of the threshold until Darla slips past them, now wearing her own clothes.
Derek finds the discarded shirt and pulls it over his head. He hears Casey enter behind him, shutting the door.
"She seemed smarter than your usual flavor of the week."
"Flavor of the past couple weeks, actually." He turns in time to see her hide her surprise behind a careful mask of indifference. He also catches a flash of hurt, and he wonders if she expects him to tell her when he's seeing someone now.
It's not like they live together anymore.
"Are you here for a reason or…?"
She narrows her eyes at him. "We were supposed to study together about thirty minutes ago. I rearranged my entire schedule because it was the only time you could meet." He heard the unspoken, 'and you blew me off.'
He grins at her. "Something came up."
Casey gives him a once over with her eye. She looks unimpressed as she says, "I'm sure it did."
It takes him a second, but then he's laughing. "Casey McDonald, did you just make an innuendo." She's staring at him furiously, but he can see the blush creeping up her cheeks.
"I'm glad you find inconveniencing other people funny. I know that you do not take your academic success as seriously as you should, but you could at least have the decency to let me know you won't be able to make it, so I'm not wasting my time waiting for you."
Derek can't help but notice there's some unexpected venom there. "Jeez, Case, chill. I didn't mean to forget about meeting up with you. Darla showed up, unexpectedly, and…," he shrugged. Maybe casual isn't as uncomplicated as he liked to believe.
"I suppose I shouldn't be surprised." The anger is gone. Now she just sounds tired.
"We can study now?" If he's ever asked, he'll deny that he volunteered to study.
"I don't know why I should bother to help you study for the test on Tuesday after today's inconvenience," Casey sniffs, and he realizes it's going to take more than an invitation to willingly study to make it up to Casey.
"Wait, there's a test on Tuesday?" She nods. "Aw, shit. I'll buy dinner?" It's the closest thing to an apology he can give, she seems to know it, because she gives in and they spend the rest of the afternoon studying.
…
A little over a week later, and they're getting their test grades back. Derek meets Casey after class, and Darla is standing there, too. "Well?" Casey prompts, impatiently taking the paper from his hand before he can answer.
Her mouth drops and blue eyes dart from the page back to Derek. "No way! Der, this is awesome." He beams.
Darla, feeling left out, peers over Casey's shoulder. "An A, nice job!" She leans in and gives Derek a big hug. Somehow Casey's generic, but over-enthusiastic praise makes him feel better than the hug from Darla. The pleased look on Casey's face falters, and she hands the test back. "I know just the way we can celebrate," she says.
He turns his attention away from his stepsister and focuses on the girl wrapped around him. "I'm looking forward to it," he says, ignoring the little twinge at the back of his mind. Carefully he disentangles himself from her (his no PDA rule still stands), and when he looks up, Casey's gone.
…
Every time we lie awake
After every hit we take
Every feeling that I get
But I haven't missed you, yet
Every roommate kept away by
Every sigh and scream we make
All the feelings that I get
But I still don't miss you yet
Only when I start to think about it
I hate everything about you
Why do I love you
I hate everything about you
Why do I love you
Only when I start to think about you I know
Only when you start to think about me do you know
I hate everything about you
Why do I love you
You hate everything about me
Why do you love me
I hate
You hate
I hate
You love me
I have everything about you
Why do I love you
Casey turns around to face them, chest heaving a little. "Well?"
"It's good," Margo says, hesitantly.
"But?"
"No buts, it's good. A little emo, but in a good way." Still, Margo is hesitating. "You just seemed to take that song to heart is all," she finally says.
Casey rolls her eyes. "Guys, I write what I feel-"
"I know, which is why I'm-Casey, is everything okay?"
"Is this about to turn into a therapy session, because if so, I think we can call band practice to an early end." Derek interrupts. Casey shoots him a glare, flinging her paper at him.
"Derek, you ass." The tears that had been threatening were gone from her eyes, though. She turned her attention back to Margo. "I'm fine, just letting out some frustration." Her eyes shoot to Derek.
"If we win Battle of the Bands, Casey, you can pay for someone to help ease out that frustration in a less emo way."
"Derek!" She chases after him, and Derek darts out of the garage, laughing.
Jackson glances over at Margo. "That may be the end of practice after all."
…
They end up getting another solid thirty minutes of practice before calling it a night.
The guys from the team come in toward the end and watch them. Even though they agreed they didn't want an audience, no one says anything since it's their house and all. They all seem impressed with their music, too.
"Honestly," Martin says, clapping Derek on the shoulder. "I thought this would be totally lame, but you guys are great." He's talking to Derek, but his eyes are on Casey. "So, two guys and two girls are you and Jackson…" he gestures between Margo and Casey.
"The redhead has a girlfriend, and the one with the webbed feet is my stepsister."
Martin makes a face, "She has webbed feet?"
Casey, unfortunately, chooses to tune into the conversation now. "I do not have webbed feet." She rolls her eyes. "Ignore him; his imagination tends to run away with him."
"Well, webbed feet or not, are you available tomorrow night?"
…
Casey declines the date, at first, but by the end of the night, she's got a date lined up for the weekend. Derek walks her back to her dorm. "What about that guy?" He asks.
"Which guy?"
"The one from your English class?"
She shakes her head. "We had one date, I hardly owe him anything."
"I thought you were still together after that. He came to watch us play." Casey shakes her head. "What about the other guy, the one who needs to get a clue?"
Casey gives him a long, hard look that he can't decipher. It does make him uncomfortable, though, for a second. "He still hasn't a clue, and I'm tired of waiting for him."
Derek's steps falter, but he catches up quickly. "So, you're moving on from him just like that?" She shrugs. "You're not even going to tell him, give him a chance to disappoint you when he fails to meet your expectations?"
Casey stops, whirling on him. "What do you mean fails to meet my expectations?"
Derek snorts. "Casey, I know you; you want the white picket fence, the 2.5 kids."
"There's nothing wrong with that."
"There's nothing wrong with it at all."
"You want some of those things," she points out, and he nods in agreement.
"I do, but I also want a challenge. I don't care about things being perfect. You want the perfect husband, the perfect house, the perfect relationship; no one can live up to that, and when they do, your expectations rise."
"You don't know me half as well as you think you do, Derek." Casey murmurs, quietly. "I have no expectations for him, other than that he would break my heart. I don't expect him to be perfect… I don't…" she huffs, running her hands through her hair. "I can't just tell him. He needs to get it on his own, otherwise; I don't know."
"You're already setting him for failure!"
"That's not it, Derek. It's just. I can't tell him I'm interested. If he's interested, he needs to figure that out on his own, without help from me."
"But you're getting tired of waiting for him."
"Maybe. Then again, I say that frequently, and here I am, still waiting."
They're both quiet as they resume walking to her dorm. "So, Martin?'
"Seems nice."
"He's not."
"He's willing to go on a date with me even though there's a possibility I have webbed feet." Derek laughs. "Honestly, Derek." She says, but she's smiling too.
a/n: Song - I Hate Everything About You by Three Day's Grace