He's sick of it.
Sick of hearing the giggles at night during their all-too frequent sleepovers, their hushed hisses and moans through his wall. He's sick of her presence, eternally mocking him. He's sick of his father's obliviousness and Nora's denial.
He's sick of seeing them in the mornings, Casey smiling in that way he wants to make her smile, Paulie's all too familiar smirk creasing her face. He's disgusted by the glint she gets in her eyes when she's turned on, sick of the way Casey tries to hide her shudder when she touches her.
Casey was supposed to be his. Casey was supposed to fall for him. It's only a cruel twist of fate; if only he'd told her sooner, if only he'd grown up a bit faster, if only he'd broken past his steely, cocky exterior and taken the chance when it was presented to him.
It's a Monday, and Casey gets home looking entirely too pleased. Paulie isn't in tow, at least, but Derek can easily imagine what's causing the giddy smile on his stepsister's face.
He sneers at her, and she ignores him. The fact that she barely acknowledges him makes his chest twist up; that's been their thing, the constant bantering and arguing, the subtle touches and not very subtle insults.
"Why are you so freaking happy today?" he snaps, as Casey hangs her coat on the rack.
"No reason," she says, but he knows better.
"What, did Paulie fuck you extra hard today?" he spits out bitterly.
Casey frowns, and Derek sighs. Finally.
"God, Derek. I know you don't like her, but the least you could do is be respectful about it. Besides, the less I'm around you, the better, right?"
She heads up the stairs, and he watches her.
"Right," he whispers miserably.
0-0
After dinner, he hears Casey's conversation, which is filled with bubbly phrases and a sickening honeyed tone, and Derek decides lovesick Casey is what nauseates him the most.
They make plans for the fifty millionth time to go out on Sunday, and Derek suddenly wishes his family was the church-going type.
He turns on his music, loud enough to drown out Casey's I love you.
But Casey stops at his door, and says bitchily, "Can you turn that down? I'm trying to talk on the phone."
"Oh," Derek scoffs, "Please, don't let me interrupt your sickening love talk."
Casey rolls her eyes, and says, "I gotta go, Pauls. A certain stepbrother of mine is being an asshole," She pauses, and huge grin crawls across her face.
"I love you too. See you tomorrow."
Derek groans. Goddammit.
Casey puts a hand on her hip. "What is your problem, Derek?"
"My problem," Derek grumbles, "is the fact that you have to act like some lovesick puppy all the damn time. Do you know how annoying that is? It's like watching a fucking lifetime special, minus the abusive husband and estranged ex-wives."
It's a complete lie, and Casey buys it, huffing as she bitches at him about how insensitive he is.
Casey's unusually cheery behavior is still unnoticed by the parental units, and Derek wonders if he has to spell it out for them.
But Casey would hate him for that and probably never forgive him, and as much as he wants to get back at her girlfriend, Derek can't stand the idea of Casey hating him. Not ever.
0-0
Tuesday night, Paulie comes over for dinner (again) and stays too damn late for a "study session" which is really a euphemism for a makeout session and heavy groping.
He hears Paulie's whispering and Casey's hushed whimpers, and he'd like nothing more for Nora or George to walk in on them in that exact moment.
It's right at that moment Derek thinks of something. Casey couldn't hate him for spilling the beans about their relationship if she didn't know he was the cause of it.
He smirks, and heads down the stairs, finding Nora. She's busy cleaning the kitchen, and Derek leans against the counter, pausing for effect before saying anything.
"Yes, Derek? Do you need something?" Nora asks.
"Casey was wondering if you could bring up some cookies and milk." He says idly.
Suspicion makes its way across Nora's face. "Why are you asking for her?"
"Come on, Nora. Do I look like the kind of guy that would pass up free cookies? Besides, I gotta get something out of the car."
Ultimately, Nora falls for it, and he hides a smirk before grabbing his keys and exiting the house.
0-0
Casey is a fast learner. It's one of the traits Paulie most admires in her; not to mention the sex is better and better every time.
She's at her peak, and Casey makes her beg a bit, because Casey has a little bit of a fetish for submissiveness, and, burying her hand the brunette's tangled hair, Paulie lets out a long sigh as her body relaxes.
Casey kisses her then, like she always does when they're finished; it's one of those long, gentle kisses that makes tingles run up and down her body.
She hears the smash of glass on the floor, and they both jump, looking into the shocked eyes of Casey's mother.
"Oh my God," Nora chokes out dazedly, gripping the doorknob so tight her knuckles are white.
"Mom—"
Nora ignores Casey's futile attempt at reaching out, mainly because Nora doesn't really want to look at her daughter anymore in the compromising position, with red lips and a flushed face and tangled hair. The door slams.
And the first thing Paulie says is, "I can't believe we forgot to lock the fuckin' door."
0-0
The last thing Casey wants to do is go downstairs and face her mother. It's cowardly, she knows, and she knows she has to deal with it sooner or later, but does she really have to do it now?
So she cleans up the mess on the floor first, just to drag out the inevitable.
But Nora hears the commotion, and at the foot of the stairs, she says quietly, "I think we need to talk."
"But the mess—"
"The mess can wait," Nora says, a little sharply, and Paulie, who's cowered beside Casey, flinches.
0-0
Paulie's never been in the basement before, and it's a little awkward, but Paulie supposes it's the only private place in the house.
Nora asks all the usual questions. How long has this been going on? How long have you been…intimate?
She lectures them too, about how deceiving them for three months was an incredibly selfish thing to do, and taking advantage of sleepovers was, at most, incredibly immature.
The good news: Nora isn't exactly pissed that Casey's dating a girl. The bad news: Nora's a little pissed about their sex life, in which Nora believes should be nonexistent.
Neither of them choose to comment on that, because it's already humiliating enough to have an parent know about their child's sex life.
Then Nora asks the worst question: "Casey, are you gay?"
It's the one thing Casey's been struggling with, the fact that she can't label herself accurately so she can have her life all neat and tidy likes she's used to. She looks down, trying to find the words to explain just how she could fall for Paulie, and can't.
"No," Casey says, very carefully, "I'm not sure what I am." The girl shifts her gaze down, and she whisperes, "But I love her, Mom. This isn't some…phase or crush, and it might be confusing but I love her, and…it's worth it."
Paulie is startled at the admission, resisting the urge to kiss her right there. She takes Casey's hand instead, squeezing it. I love you too, Case.
Nora sighs, a little shakily, but remains composed. "I have to admit, Casey, this is a shock," she says, and glances over at Paulie, "but I can't say I don't support you or Paulie."
Paulie smiles, grateful for that.
"And after I tell George about this…Well, I'm going to omit a few things, of course. But we will be implementing a few rules. Does that sound fair?"
And really, what can either of them say except yes? Casey was lucky Nora was willing to accept it.
Casey walks Paulie to the door, fully aware of Nora's eyes on them. They can only exchange pecks on the cheek and smile nervous little smiles at each other.
And then Casey closes the door.