[Bellatrix/Lucius]

She threw her weight into him, forcing his back to scrape painfully against the rough stone wall.

"You're out after hours," he said, voice calm despite the wince that adorned his features. She threw her head back, realising a harsh bark of laughter.

"You're not going to give me detention, are you Lucius?" she asked, features twisting into a mockingly sweet expression.

He smirked, about to reply, but her lips were already crashing into his, her teeth breaking skin, her hands gripping his biceps, effectively pinning him in place, and sure to leave bruises in the shape of her fingers.

"You need to learn when to shut up," she hissed, her teeth scraping the shell of his ear. She bit hard into the flesh just below his jaw, her fingers loosening their hold slightly, and he took the opportunity.

Her back collided with the wall, hard, and a small gasp escaped her lips. A leg wrapped around his calf, and she grinned up at him, all teeth, a predatory look in her hooded eyes.

"Would you do this with dear little Cissi?" she whispered, grin widening. The image of a Doxy about to bite flashed through his mind.

He pushed away from her harshly, leaning against the opposite wall, breathing heavily.

"Don't talk about her like that," he hissed, but the words sounded weak to his own ears.

"Why not?" she taunted. "Do you love her? Care about her feelings?"

"You know I do."

"Then why are you here?" She folded her arms across her chest, looking smug; she clearly thought she had won this.

He struggled to formulate a reply; mouth open, trying to form words that he didn't yet have. Her laugh echoed through the corridor, and, distantly, he worried that someone might hear.

"You don't seem in any hurry to leave." Still laughing, she pushed away from the wall and disappeared down the corridor, hips swaying with every step.

Somehow, he was left feeling wronged.

.oOo.

The next morning, that feeling became justified.

He took his usual seat at the Slytherin table, frowning when all discussion around him stopped abruptly.

"What's going on?" he snapped, glaring at those around him.

"As if you don't know," a girl a few years below him snapped - she was Narcissa's friend, he knew that much. The Greengrass girl? Rowle?

He frowned slightly, noting the seat next to her was empty, and scanned the length of the table for Narcissa. His eyes landed on Bellatrix instead, and she smiled brightly at him, seeming genuinely happy. He felt dread pool in his stomach.

.oOo.

It wasn't until later in the day that he managed to corner her. The good mood from breakfast seemed to have lasted, and that worried him more than anything else that had happened today - more than the odd looks he'd been receiving from his housemates, and a few braver members of other houses; more than Narcissa's unexplained absence.

"Ah, Lucius," she practically purred, stepping closer to him. "To what do I owe the pleasure?"

He didn't say anything, simply gripped her arm tightly and dragged her into the closest empty room, shoving her through the door and locking it behind them.

"Why?" he hissed, glaring down at her.

"Why what?" she asked innocently, her voice sounding strange distorted by such a tone.

"Why have you done this?" he hissed. "Do you enjoy causing other people pain so much?" He laughed then, the sound harsh and broken to his own ears. "Of course you do. How could I forget, you're a sadistic little-"

"Me? None of this is my fault. I was just looking out for my sister," she said.

"Your sister? You can't honestly think this shows how much you care for her."

"I care more for her than you."

"How could you possibly-"

"Why are you here, Lucius?" she repeated the question from last night. "Have you spoken to her at all today? Do you even care that this is affecting her, too?"

"I-"

"Why are you always seeking me out?" She pulled away from him and walked calmly towards the door. "Really, Lucius," she said, wordlessly unlocking the door, "someone might mistake it for caring."