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The house is a flurry of activity, as it always is when Casey and Derek are home. The smell of something burning wafts from the kitchen, and Mrs. McDonald's voice rises above the din, shouting instructions to her husband. Casey and Derek are in the living room, the TV blaring some mindless reality show, but neither of them is paying attention. Casey is perched on the arm of the couch, her phone clutched in her hand, her thumbs flying over the screen. Derek is sprawled out on the floor, his back against the coffee table, a sketchbook propped on his knee. He's drawing, his hand moving with a life of its own, the charcoal scratching against the paper.
"Case, I need to talk to you about something," Derek says, putting down his sketchbook. He runs a hand through his messy hair, leaving it standing on end.
Casey looks up from her phone, her eyebrows raised. "What's up?" she asks, her voice laced with concern. She knows that tone, and it's not one that bodes well for a casual conversation. Derek takes a deep breath, his eyes flicking to the door as if expecting someone to walk in and save him from this conversation.
"It's about Truman," he says, his voice low. "He wants to take you to the prom."
Casey's expression darkens, and she shakes her head. "I know," she says, her voice tight. "I already told him no."
Derek nods, understanding passing over his face. "This isn’t… I mean, to other people, this is… Case," he starts, his words tumbling out in a rush.
He's flustered, his cheeks flushing pink. He doesn't do well with these kinds of conversations, and Casey knows it. His stepsister nods, carefully reaching over to cover his hand. The family doesn’t understand. But it’s not a difficult concept. She smirks at him as he fumbles over his words.
"I’m not crushing on your friends anymore," Casey says, her voice steady and sure. She's not ashamed, not embarrassed. She's just stating a fact.
"No, you are not," Derek agrees, a small smile playing on his lips. He's proud of her, proud of how she's grown, how she's learned to stand up for herself.
"And are you alright with that?" Casey asks, her voice softening. She's always been protective of him, always been his rock.
Derek nods, flipping his hand over but not dislodging hers so their fingers can intertwine. "That was a long time ago. I just thought of you as a sister," he says, his voice firm.
"Stepsister," she emphasizes, a playful glint in her eye.
"Not the same thing," Derek agrees, a soft smile on his face.
"Not in the slightest," Casey replies, her voice mock-serious.
The front door slams open, and in walks Emily, her eyes scanning the room until they land on Derek. She smiles, a predatory expression that makes Casey's stomach churn.
"Derek, I was hoping I could talk to you," she says, her voice sweet as honey.
Derek looks up at her, a blank expression on his face. "About what?" he asks, his voice guarded.
Emily saunters over, perching on the arm of the chair opposite him. She leans in, her voice a low purr. "I want to take you to the prom, Derek," she says, her eyes never leaving his.
Derek's hand tightens in Casey's, and she can feel the tension radiating off him. He takes a deep breath, his voice steady when he speaks. "I'm sorry, Emily," he says, his voice polite but firm. "I already have plans with Casey."
Emily's eyes flick to Casey, a look of disgust passing over her face before she schools her features into a neutral expression. "Oh, I see," she says, her voice tight. "Well, if you change your mind, you know where to find me."
With that, she stands up, her heels clicking on the hardwood floor as she stalks out of the room, leaving a tense silence in her wake.
Casey looks at Derek, a small smile playing on her lips. "Looks like it's just you and me, stepbrother," she says, her voice light and teasing.
Derek smiles back, his eyes crinkling at the corners. "Wouldn't have it any other way, stepsister," he replies, giving her hand a squeeze.