A.N - Hey, all. I'm hoping that this one-shot will kinda serve as my intro to fanfiction, Mortal Instruments style. So let me know what you think? I kinda have an idea in mind for a story, but I just wanna know how you react to my writing first. xD

This is post City of Glass by the way. So if any of you havent read it. There may be slight spoilers. I don't think they are, but just to be sure. :D

Disclaimer: I own nothing. All characters, places, etc belong to Cassandra Clare. :)


MORTAL INSTRUMENTS

Green-Eyed Demon

"Remind me what we're doing here again?"

Pandemonium, apparently, was the place to be that night. Mundanes gathered in groups along the wall of the club, each wearing some variation of vibrant colours, sequins and party clothes. The bright light washed over the crowd periodically, causing glints of silver to wink in the otherwise dark night. The Shadowhunter clan had been there all of five minutes, but the line was long and Jace was already bored.

He hooked his arms around Clary's waist, pulling her closer to him as he placed a distracted kiss on the curve of her exposed neck.

"I can answer that in one word," Alec said, rolling his eyes before he narrowed them into a glare at his sister. "Izzy."

"You'll thank me when we get inside," Isabelle shrugged.

"If we ever get inside," Jace mumbled.

They'd been back in New York barely two days, after the thrill ride that was their visit to Idris. Approaching the Institute, Jace had been the first to speak.

"Institute, sweet Institute," He quipped, a brief smile overtaking his face.

"Institute, Schminstitue," Isabelle countered. "I say we dump our stuff then head on out. Pandemonium anyone?"

"Oh, shut up," Clary elbowed her boyfriend gently in the ribs. "If you didn't want to be here, you could have easily spent the night with Church."

"And miss the chance to see you all dressed up and sexy?" Jace spun her around until the rough brick wall was pressed into her back and he had her hands pinned loosely either side of her head. "No chance."

He dipped his head and captured her lips with his; slowly and languidly, they kissed, uncaring of the eyes on them, as both were lost in each other. Clary's hands raised to entwine around Jace's neck as his slowly ran up her sides, sending hot bursts of electricity shooting along her nerves. His warm fingers spread across her waist where her top had ridden up, anchoring her to him.

Their kiss continued, ignoring the faint hum of disapproving voices in the background, right up until someone pushed through the throng of people, knocked Jace and sent Clary's head forcefully backwards as it whacked against the building with a dull thud. She took in breath sharply, more out of surprise than pain.

"Hey, watch it!" Jace's anger was instant and one hand was removed from Clary's waist as he used it to swear at the jerk that'd pushed past. "Asshole!"

The Asshole glanced behind him; the grin on his face stretched his cracked, blue lips up to meet the pure emerald of his eye – excluding the pinprick drop of scarlet for a pupil – and revealed a mouth full of black, crooked teeth. His glamour, however, revealed nothing but a normal, begrudging-to-admit good-looking boy. He winked at Jace who cursed in response.

"Demon." The word was laced with acid undertones and Jace's hold on Clary grew unconsciously tighter as his eyes narrowed at the Demon. "Clary," Jace directed his golden-eyed gaze at her, softening as he noticed her fingers gently probing the sore spot on her head. "You stay with me, okay? Tonight, you do not leave my side."

A tense silence enveloped the four Shadowhunters. Alec and Isabelle watched on as Jace's eyes focused on Clary with a look that was both worried and protective. Clary, meanwhile, was annoyed. Her eyes narrowed at Jace and her hand fell from her head to her side, balling up into a tight fist. Around them, the crowd of people knew better than to interfere: there was a sense of danger emitting from both the golden haired boy and his girlfriend that screamed 'do not interrupt'.

"What?" One word – one syllable – and still it managed to contain all of Clary's anger.

"You heard me." Jace got closer to Clary, his lips mere millimetres from her ear. "Stay. With. Me."

"You have got to be kidding me." Clary exploded, pushing Jace away from her. "After all I've learnt these past few weeks – all we've been through. You treat me as if I'm nothing more then a mundane!" She paused for a moment, eyes wide and gleaming as she breathed in harshly. "You still don't accept me as one of you."

The realisation hurt and, when accused of it, Jace didn't say anything. He gritted his teeth and looked at the dirty, New York sidewalk.

"Well, here's something new for you: No."

Clary's hand snaked around Isabelle's wrist, encountering both warm skin and the cool metal of the bangles she wore, before pulling her gently and pushing through the crowd to reach the bouncer and the doors to the club. Glancing behind her, Isabelle shrugged at her brother as she was pulled along before she caught a glimpse of Jace's shocked, handsome face and laughed prettily.

Oh yeah, Jace and Clary were perfect for each other.


By the time the boys made it into the club, Jace's shock had strengthened into fury, hot and potent. She was right, of course. He hadn't seen her as a Shadowhunter; he had thought of Clary as being blind to their world and untrained as a fighter, as she had been when he'd first met her. But to walk so unabashedly into a potentially dangerous situation was just plain … idiotic.

Clary can handle herself, Jace repeated as a mantra, over and over in his head. He was damn proud of it - that she'd learnt so much in such a short space of time. But it didn't ease the worry, not one bit.

Inside, the club was awash with fluorescent; lime greens and candy-apple reds rained over the writhing, sweaty bodies on the dance floor as music pulsed through the speakers. Immediately, Jace began to seek out Clary. He owed her an apology, among other things. He was man enough to admit that maybe he'd overreacted.

"Isabelle," he shouted at whom he regarded as his sister, to be heard over the pounding music. "Where's Clary?"

Annoyed, Isabelle glanced up from her newfound date for the evening and pointed at the dance floor. "Apologise." She demanded. "You were being an idiot."

Jace rolled his eyes. "Thanks, Izzy." He turned and followed her finger to find Clary.

He couldn't help the smile that took over his face when he saw her. Around Clary, his badass, don't-even-think-about-it persona disappeared. Just one glimpse of her fiery red hair and her pale, porcelain skin and he was lost. One look, however, at the distinctly masculine hand snaking around her waist had his vision tinting an angry red and the urge to fight rushing to the forefront of his mind.

Clary had her back to him, but the guy … him, Jace could see. He was tall and had dark hair that fell into his emerald eyes with what looked to be a small red point in the centre under the flashing lights. They guy lifted the corner of his blue mouth in a smirk that could rival Jace's own and revealed the same set of decaying teeth that Jace had seen once already that night.

His girlfriend was dancing with a demon?

Jace's eyes fell shut. He was fighting against the urge to pull that thing out of Clary's arms and pound its face in – a defensive move that he had justified to Clary being his little sister before and had no such excuse now. He'd finally talked himself into just going over and apologising to Clary, maybe shoot a few scathing 'watch-your-back-later' glares and not pull out a weapon in a public place when he opened his eyes again to find that the pair had vanished.

"By the Angel!" Jace ran a hand through his pale, blonde hair in frustration. "If she does something stupid just to get back at me, I swear on the Angel I'll …"

He trailed off as he found her recognisable red hair, bright against the dark wall she was leaned against. Jace watched as the demon leaned into her neck, his lips getting closer and closer to her skin.

"Screw it," Jace mumbled, throwing out all his previous, ridiculous notions of peace and non-killing. That demon was getting its ass handed to him. Big time.

The anger was all consuming. Jace and every bone in his body were pissed as hell. Especially when Clary leaned up, placed her small hand against the back of the demon's head and whispered in its ear. She said one word and Jace froze as he followed the word her mouth formed.

"Azriel."

The next moment, a shock of blue light accompanied the glint of a crystal blade and Clary's face furrowed in concentration as she pushed the sword into the demon's chest.

Jace was closer now, and could hear the demon's reaction.

"Bitch," it spat at Clary, who replied by pulling the sword free again.

"That's for shoving my boyfriend," she spat before adding under her breath, not unlike Jace, "asshole."

The demon folded in on itself. Thick, black gunk spread along the floor as the demon disappeared, spreading and drying to form a dark powder before the demon was finally gone.

"Ew," Clary muttered, inspecting the damage done to her shoes as she put away the seraph blade again.

"Clary!"

She looked up sharply at the sound of Jace's voice. "Look, Jace. I can explai–"

Her words were cut off as his mouth fell on top of hers. The hard planes of his body moulded against her curves and settled her firmly against the wall. They pulled apart and Clary gasped for the air that had been knocked out of her as Jace pressed kisses along the column of her throat.

"That," he muttered into her skin, "was amazing."

"Figures that me killing a demon gets you all hot and bothered."

Jace pulled away and grinned at her, showing her his teeth - the endearing chip in his tooth was, as always, the only non-perfect thing about him. "Well, yeah," his grin turned smug. "I taught you everything you know."

Clary rolled her eyes. "Yeah, well," she pushed him away gently. "I hope I proved to you that I am not just a mundane. I can … shadowhunt with the rest of you."

Jace nodded eagerly before a dark expression settled on his face. "I hope that you don't intend to let every demon you kill get that close to you before doing so, though."

"Why?" Clary questioned, a smile picking up the corners of her pink lips. "Jealous?"

Her response was another quick kiss. "It drove me crazy," he admitted. "Before … with Simon," he continued. "I could justify all this protective jealous stuff as being your brother. But now …"

"Oh please," she rolled her eyes before smiling at him. "You're way too full of yourself to think that I could ever like anyone else."

His smug grin was back in place. "I'm pretty amazing, it's true."

"I bet you know how many girls can't take their eyes off you right now." Clary countered.

"Eight." His response was immediate. "Nine if I count you." She was blushing again. He loved that blush. "So, why bother with all this?" He asked in confusion. "If you didn't think that another guy would make me jealous."

"Because you pissed me off."

Jace blinked. "Fair enough."

"And," Clary continued, "because the best way to get you jealous and annoyed isn't for me to go off with random strangers," she tried not to show the tingle of delight she felt when his eyes hardened. "It's for me to steal your kill." She stared him in the eye. "And you were going to kill him tonight."

Jace groaned. "By the Angel, you're good."

"Thank you." Clary smiled. "You taught me everything I know."

Laughing, he kissed her again. He'd never tire of the feeling of her perfect lips moving with his.

"I love you, Clarissa Fairchild." Jace's voice was deep, every word ringing with perfect clarity and honesty.

"I love you too," Clary responded in turn. "Jon-"

"Jace," he murmured, interrupting her with a chuckle. "I'm just Jace."

"Yeah," Clary mumbled in return, her eyes locking with his as she smiled, brilliantly, at him. "I love you too, Jace."