Quality Time

A TMI One-shot by ChronicLegCramp-Since'99

*Disclaimer: The Mortal Instruments and all its characters belong to Cassandra Clare, respectively*

Sebastian was in the process of getting changed, his arm outstretched for the pair of jeans lying on his unkempt bed, when he sensed his bedroom door creaking open. He looked over at the door, repressing the smirk threatening to morph his face as his sister edged into the room, closing the door behind her.

"Yes?" Clary swung around, muffling a noise of exclamation before her face flushed scarlet and she looked away from his near-nudity. Sebastian made no move to cover up, merely continued staring at her, patiently waiting for her to explain herself.

"Sorry- I'll go…" she muttered, backing up.

"No need. What did you want?" the ivory haired boy asked, amusement and something else flickering in his onyx eyes. His sister glanced back at him reluctantly, her fiery curls hanging hectically around her shoulders as if she'd been running or had just woken up. Sebastian liked the thought of his sister in bed rather too well, although it wasn't he who was bothered by it. Clary's tired emerald green eyes faltered under his gaze as though she could tell what he was thinking.

"I was looking for Jace," she told him in a wary voice, shifting her weight, evidently uncomfortable.

"Really?" Sebastian raised an eyebrow and crossed his arms over his smooth marble chest. "Jace's bedroom is down the hall, but you already knew that,"

"Yeah, he's not in his room-" the redhead began again, a slightly petulant pout growing on her lips but her brother cut her off.

"Must we do this, Clarissa?" his tone was chiding as he finally retrieved his jeans and stepped into them, sliding them up his legs and deliberately leaving them undone and gaping open.

"Do what-?"

"Why is it that you're so desperate to go prying through my things? What do you think you'll find?" he paused expectantly, but Clary said nothing, her face tight as she returned his gaze. "That's the exact look our father used to wear once he was done whipping me," he'd said it matter-of-factly but his sister flinched, balling her hands into fists.

"Stop it," she shook her head, her forehead creasing in anxiety.

"Stop what?" Sebastian replied, stalking across to where she stood avoiding eye-contact. "Telling you the truth?"

"I don't know when you're telling the truth," she said quietly, tensing and looking down as he invaded her personal space. "I don't even think you know. I guess that's why you're so good at manipulating people,"

"I know you prefer the lies," he said just as quietly, brushing her red hair over her shoulders and resting his hands there, fingering the thin straps of her vest top. When he saw her open her mouth to argue, he continued. "Tell me; are you glad that I am your brother and not Jace? Or would you rather have had Jace for a brother than me?"

"Neither," Clary answered, stiff under his touch.

"But if you had to choose," Sebastian pressed, forcing her to look up at him by cupping her chin.

"…You. You are my brother. Nothing will change that," she said in a regretful voice, seeming as if she were finally admitting to herself that they were kin. Sebastian's pretty plush mouth quirked up on one side.

"How truly heart-warming it is to hear you say that, dear Sister," he whispered darkly, twisted humour glinting in his black eyes.

"I'm in love with Jace- I'd never wish he was my brother. Not in a million years," his sister bit out scathingly, a flash of defiance in her emerald gems; the white-blond narrowed his eyes and dropped his hand from her chin. "You didn't really think my choice had anything to do with you, did you? What's the matter, don't like the truth?" Sebastian's hand shot out to close around her neck like a vice, his nose flaring and his eyes boring into hers. However, as quickly as his rage had come, it receded, his sharp, angular features turning thoughtful. And then he released a low satisfied chuckle. Loosening the grip on her throat only slightly, he leaned down so that his lips were hovering by her right ear.

"How alike we are…" he breathed softly, before swiping his tongue from her jaw to her temple and chuckling again. Clary immediately started struggling, trying to shove him away but his hand tightened around her neck once more. "Now, now, Clarissa. Behave," she went still as his eyes laughed down at her with unmistakable intent.

It was then that a hesitant knock sounded on the door. Sebastian roughly covered her mouth with his free hand, taking no notice of the fact that her nose was partially smothered by his palm.

"I'm getting dressed- is it important?" he smoothly called towards the door.

"Clary's missing," they heard Jace say, his tone worried. The person in question slapped Sebastian's chest frantically and he dropped his hand from her face almost automatically. She gasped, sucking in a lungful of air but when she made to speak, he gave her a warning look. "Did you hear me? I can't find her anywhere…" the white-blonds expression turned from irritated to amused in a split-second, as he smiled slyly down at the redhead.

"Act natural, wont you?" he murmured to her before stepping away and saying loudly, "Shes in here,"

"What…?" the door opened quickly and Sebastian waited until Jace came into view before zipping up his jeans with a lewd smirk on his face. The boy with the wavy golden hair glanced between the siblings with a strange look on his face, not unlike suspicion.

"What are you doing in here?" he asked Clary casually.

"Yes, what are you doing in here?" Sebastian echoed faux-innocently. "You never did say,"

"Looking for you," she told her boyfriend lightly, ignoring her brother. "Wanna watch a DVD?"

"…Sure," Jace replied belatedly, looking vaguely sceptical.

"That's a shame. We were having fun, weren't we Clary?" Sebastian said in a meaningful tone that made the angel boy's frown deepen, his gaze on the redhead.

"Well, none of us are going anywhere," she said, voice mildly tinged with hostility before she pushed a confused-looking Jace back out into the hall.

"Clarissa," she paused on the threshold, not looking at her brother. "Hurry back," he smiled, non-deterred by her vivid glare.

"In your dreams," she said simply, mirroring his smirk briefly before slamming the door shut on her way out.