a/n: uh, hello? I'm going to gush right now, I MISS THIS FANDOM SO MUCH. I've been a little obsessed with LiveJournal and The Vampire Diaries and started writing this today when I realized that I couldn't remember the name of that episode in which Casey's dad comes over and then I felt terrible because it was such a Dasey episode and the fandom has only been my life for like two freakin' years, so how could I possibly have forgotten? D: This is not a huge multi-chapter fic (I know I'll be lynched if I tried that now), just maybe one or two chapters more. God, I know I'm really bad with the updates, that does suck.

disclaimer: disclaimed


"She kicked you out?"

"Marti," Casey gripped the phone tighter, "not so loud!"

She could practically see Marti rolling her eyes, in that god-I'm-related-to-her sort-of roll, which she probably learnt from Derek, except his was more of a god-I'm-related-to-her-by-law sort of roll. She'd lived with them for over four years, okay, she could totally tell the difference.

"Casey, you need to chill, okay? Dad and Nora are out with the Davises and they'll spend fifteen minutes eating and approximately another hour-fifteen arguing over the bill. Edwin and Lizzie aren't back home for the holidays yet, and Simon's still busy loading Edwin's scanned naked baby pictures up on facebook. It just requires pressing buttons monotonously, and the kids' proving to have inherited most of my genes, fortunately. And there's no one else around to hear."

"Do you still lock your door when Conner comes over?"

Marti snorted, "God, yes. Dad refuses to listen to reason, so he has to learn the hard way that I'm not six anymore."

"Then the sound-recorder that George planted in your room is recording our conversation as we speak."

There's a minute of outraged silence and then scrambling sounds followed by the sub-human scream that probably indicated the finding of the guilty device, "you knew about this?"

"What— no, I just…"

"After all that I've done for you? Like being the only Venturi to not have used your bra as a slingshot— don't ask about dad, I don't think you want to know. And never once mixing itching powder in your bath salts— except that one time, but I didn't exactly mean to and you're always telling me how it's the thought that counts. And I didn't allow Derek to plaster missing person posters all over town from that time you dyed your hair blonde because you thought it would help you discover yourself and…"

"You do realize," Casey said wryly, "that you define everything you've done for me in terms of negatives."

"The point is," said Marti, and she could feel the younger girl's glare cutting across the miles between them, "I could have and I didn't. And this is how you repay me? Derek would've told me."

Even after all this time, she still felt that familiar annoyance at the suggestion that Derek might, in any way, be the better sibling, "you do realize it was Derek's idea, right? Because George's mid-life crisis involves tight leather pants, 'George of the Jungle' performances, and a general denial of the existence of any decade beyond the 1980's. And they didn't have these things in the '80's."

"If you weren't in love with him, I swear I would totally…"

"It's wrong to swear," Casey interrupted piously, "and for the last time, Marti, I'm not in love with him! I don't even know what got that ridiculous idea in your head in the first place."

"What are the property prices of the real estate market inside your head? In spite of all the crazy, I think it might actually be a nice place to live in; secure, happy, completely freaking oblivious."

Casey rubbed her hand against her forehead tiredly; she so did not have the time for this, "what did I tell you about incest?"

"Fun games for the whole family?"

"No, Marti, it's against the law."

"And how many laws has Derek broken till date?"

From the underage drinking onwards? God, that was a good question, but this was different. It wasn't like pretending to be a hot professor to pick up all the wide-eyed freshmen with angsty student-teacher fantasies. She wasn't sure there was a law against that, but with Derek in the world, there should have been one. The jerk, he'd ruined his little, innocent baby sister by being the way he was, if her completely unholy line of questioning was anything to go by.

"The point is," she said, tenaciously coming back to the original topic, "I still have no place left to go."

"What did I tell you about crushing on your roommates' boyfriend? Especially, when your particular form of crushing ends with people in hospitals nursing third degree burns because you dropped hot water on them."

"That was about three boyfriends back, and they weren't third degree burns, just like, one and half degrees or something. And I wasn't crushing on this guy. They just…they never shut up, okay. And they really didn't care that I could hear every single thing, because- fun fact- we live in a single freaking room, not a multi-storied building. And..."

"You need to get laid."

"Marti!"

"Speaking of getting laid— oh my god, you're at Derek's flat, aren't you? That's where you've decided to stay?"

"What, no," Casey hurriedly moved away from the doorstep. Was there some sort of phone GPS system that gave you the exact location of the person you were talking to? "I was just…"

"Hoping I'd make you feel better by telling you it's not like you have an option and it's the most logical choice, blah, blah, blah. Well, I'm not- you do have an option; you can always come back here to complete your research on Llamas or whatever. But you'll choose Derek. Because you're in love with him."

"Lacan," said Casey, "and you know I can't come home. It's…home; the last time I was 'researching' there, someone pulled the plug on my paper on the comparison of the Great Depression to the economic meltdown of 2008, to hook up her hair-dryer. And I finally had to write my paper on 'Why the original Wall Street was better than the 2010 version', a day before the deadline."

"Think of it this way," Marti cut in hastily, "at least there was a lot of potential material on that one."

"So, I actually have nowhere else left to go."

"Except," Marti's voice carried, what seemed to Casey, a completely unwarranted amount of glee, "Derek has a live-in girlfriend too. What makes you think she won't throw you out?"

"Because," said Casey primly, "I'm family. If she does throw me out— well, there can't possibly be a future for them anyway. You don't marry an individual, you marry the family."

"They're not marrying, so, basically, she isn't sleeping with Derek, she's sleeping with the family? Like incest?"

"Marti!"

"Whatever, Casey, you need to ring the bell. Is your trench-coat brown?"

"Black," said Casey automatically, "wait, how…"

"Casey McDonald: Failing Subtlety since 1989."

"I'm going to go," she said, before she lost her mind. Or her nerve, "just don't tell George I told you about the recorder, that probably broke some Universal Code of Ethics for Step Children."

"Oh, I won't," Marti sounded grim, "or Derek either. Normally I would think of some suitable revenge, but I don't even need to, since you're there."

"But I'm not going to antagonize him at the moment, I really need to get my work done, Marti, I'm not even…"

"Oh, that's all right," said Marti, suddenly cheerful, "you're standing at his doorstep. That's enough. He deserves this for plotting with dad behind my back."

She banged the phone mid-way through Casey offended squeal.

xx

He slammed the door on her face.

She allowed herself a full minute of outrage, and then resumed knocking. Harder. How dare he?

The door swung open, the blonde girl dressed casually in an oversized shirt with the Queen's logo (Derek's, then) looked at her with polite interest.

"I'm…"

"…just leaving," Derek interrupted from behind, "I told her we didn't order McDonald's. It's probably a mistake."

The girl looked back at her, what was her name again— Aimee, Ashlee, Toree?— looked back at her, "Sorry," she said, and of course, she would have an English accent, "we didn't order anything actually."

"I'm not…"

"…going to get full salary for the wrongly delivered order," Derek interrupted again, "I sympathize, but out of general sense of principles, I can't really pay you for this."

"What principles?" she retorted, before the idea of being the better person could fully form.

The blonde girl – Samree? Was that even a name? — looked at her with mild surprise, "maybe you could check the order again? I think you have the wrong address."

"I'm not selling anything!" she exclaimed, and how was it that he could still reduce her to this after all that time? "I'm Casey McDonald, therefore his utterly lame pun, Derek's stepsister."

"More believably," Derek said, he'd moved a little to the side so it's not like she could possibly not notice that he was shirtless (he'd given that girl the shirt right off his back? God, could he get any more high school?) "She's some starlet looking to make it big in the city. You can try sleeping with the assistant director, that's me, but looking at your face I wouldn't say the chances of it are too high. Or anywhere within the probability range of 0 to 1. Which is the entire range of probabilities, by the way."

"I know that," she snapped, more affronted by the dig at her IQ, "not all of us were counting on our fingers till the tenth grade."

"No," he said comfortably, "some of us lost count. And some of us could probably count it on one finger of one hand. If that"

She didn't know what he meant, probably something dirty, knowing him, so she let it slide, "and I can't believe you said that. What is wrong with you?"

"I can't believe you blushed at that," he countered, "seriously, if I were your boss, I would be worried about your prospects as a healthy, functioning member of society. That built up frustration is probably going to explode someday, and then you might even get your old mail that I've been re-directing to the London Asylum. By the way, that William guy, he's gay. No straight guy sends letters on floral notepaper. Scratch that— no straight guy sends letters."

"You've been doing what?" no wonder she hadn't gotten any of them, the jerk "and he's not. He's just not a raging Neanderthal like some people I could mention."

"Suit yourself," Derek sighed dramatically, "just don't come to me for chocolate ice-cream when you realize that twenty years later, and you have to the answer when the kids ask what their daddy is doing with that other man."

"So," that girl was still here? "she is your step-sister?"

"Till the law changes and allows the exclusion of unwanted step-siblings from the family circle of your dad's second marriage— probably."

"I'm Casey," she said again, and refrained from gritting her teeth, so really that had to count for something, "Derek's stepsister."

"I'm Megan," said the blonde girl (oh, so none of the double ee's then, darn it) shaking her hand, smiling, "Derek's fiancé."


tbc