Disclaimer: I do not own the Mortal Instruments series, nor any of the characters. The Mortal Instruments is owned by Cassandra Clare, I merely do this to entertain. Also, no, this is not a Clabastian fanfic. No offense to supporters out there, but I'd really appreciate it if Sebastian were to magically disappear off of the edge of the earth. Really sorry for the late update, I've just been reeeeeally caught up with school work lately. Stupid procrastination.

Clary woke to find herself in a cell. It was dark, and the only source of light was from the barred window high on the wall on her left, and she could see that it was night. It took a while for her vision to accumulate to the darkness, but once she did, she realized that she wasn't alone. There was a dark and hunched mound in front of her. The moonlight reflected off of the thing, and she saw a flash of blond hair. Not a thing, she thought, her heart leaping, Jace.

Clary immediately surged forward, but with a cry, she was yanked back. She looked down at her arms and saw that they were shackled by manacles, their chains connected to the wall. Her feet were only the same. Her wrists were bleeding from where the metal bit into her skin, but she barely felt it. Instead, her eyes were trained on Jace's unmoving form, her gaze never wavering.

"Jace," she whispered. "Jace…..Jace!" He only shifted and moaned, but did not wake. Clary sighed in relief. At least she knew that he was alive. She leaned back against the stone wall, shivering at the coldness that breached through her clothes and onto her skin. Her eyes fluttered shut for a moment, her heart racing, her mind racing with thoughts. How was she going to get them out of here? How long did Sebastian plan on keeping them? How long until he killed the both?

The grim thoughts forced her eyes open. She turned her head to look at the night sky. The spots of white surrounding the bright moon. Clary stared for what felt like hours, sleep unable to overcome her. After eternity, Jace stirred and brought his head up groggily, squinting his eyes against the dark. When his eyes adjusted as well, his head whipped around, studying his surroundings. He froze when his gaze landed on Clary.

He squinted, as if to make sure that she was really in front of him. "C-Clary?" he asked in a hoarse whisper.

"Jace," she sobbed. The sound of their shackles rattling filled the air. Emotion filled the air as each of their desperate attempts to get closer to each other failed. Even after her wrists were rubbed raw and even more bloodied, she still struggled to surge forward. A chuckle came from her right, and both of them gasped and stared at Sebastian, studying his fingernails, standing casually behind the bars as if this were an everyday event.

"You can stop with your futile attempts. Sooner or later, they'll harm you more than they will help."

"Sebastian," Jace growled. Clary glared at the demonic boy, wondering how she could be related to him.

"Hello!" Sebastian waved a hand at them cheerfully. "I see you've taken notice of this little….predicament that you're in. Pity, isn't it?"

"By the Angel," snarled Jace, "What the hell is it that you want, you arse?"

Sebastian's eyes narrowed at the insult, "Why, Jace, no need to be rude here."

Clary was tired of their exchange, so she whispered sharply, "What do you intend to do with us?"

Both of their heads jerked towards her, as if noticing that she was chained there as well, and Sebastian laughed. Its sound was deep and rich and echoed off of the molding brick walls. "'What do I intend to do with you?' That's the real question, isn't it?" Then, he reached into his right pocket to fish out a set of keys on a rusted ring. Finding the correct one, he jabbed it into the lock, and the door opened with a creak. Walking in, he neared Clary, and her breath hitched.

Jace's eyes widened as well, "I swear, if you hurt her-"

"I don't believe that you're in the position to question me, much less threaten me at the moment," Sebastian said cooly, amused. Jace growled again, and jumped forward, straining against the metal that kept him from closing the short distance. There was a loud crack; one of Jace's wrist bones breaking. He gasped, but didn't give up.

"Stop it!" she cried. She couldn't take it anymore, Jace getting hurt for her. She looked him dead in the eye, pleading for him to stop. He stared at her for a moment, reluctantly backing off. Clary sighed in relief, before she remembered that Sebastian was still standing next to her. She jumped to the side, eyeing him warily. Raising an eyebrow, he crouched until his face was level with hers. She could feel his breath on her face, and it took all of her will not to lose it right then and there. Sebastian smiled softly at her before speaking softly and slowly.

"Or what?"

"O-Or….." Clary couldn't focus. Her heart was racing, and her head had started to pound. Curving her neck, she bowed her head down, gritting her teeth, praying for the pain to go away. there was a breeze beside her, and the air suddenly shifted. Opening her eyes up in confusion, she finally let out the scream that she'd been fighting so hard to control. Before her, Sebastian was poised over Jace, that very dagger positioned at his neck.

He looked back at her, and Clary could see Jace look defiant about his current situation. "Or what, Clary?" Smirking, his hold on the knife tightened, and a bead of blood grew at the base of Jace's neck. Clary let out a whimper, and Jace stared at her, his eyes sending her a message, as if he knew what she were about to do. Don't, they said, Don't be stupid.

I'll be stupid when I want to be stupid, she thought back. Shooting her gaze back to Sebastian, she said with a shaky voice, "Deal. I want a deal." When Sebastian merely stared at her, she added with a deep breath, "Just one condition." Clary added this last part forcibly, enunciating every word carefully. " Don't. Hurt. Jace."

He slowly stepped away from Jace, who's blood was trickling in a thin line down his neck. "Just to be certain, what would this deal be promising?"

Her eyes narrowed, and she blocked out the sight of Jace's eyes pleading for her to shut the hell up. "You know what I mean," she muttered softly.

Sebastian's eyes glittered darkly. Shit. "Well, if you mean what I think you mean, then yes. I'd have to be an idiot not to refuse that wonderful offer."

"Not that you aren't one, " she said under her breath. Bad choice. His eyes narrowed, and he struck her with his palm. It left a stinging spot on her cheek, and Clary could already feel a welt rising. All the while, Jace was busy shouting and fighting against his confinements on the wall opposite of them, but they paid him no mind.

"And how would I know that you wouldn't back out of this little promise?"

Her eyes met his carefully, and despite the raging emotions inside of her, her voice was clear and sure. "I swear it. On the-"

"NO!" Jace interrupted her before she could finish, his expression frantic and desperate. "Clary! What the hell are you thinking?! I can't let you do this, you know I can't. I'm a shadowhunter; I can take a few hits. You-"

"I am a shadowhunter too. If you can take some blows, then I can too, can't I?" Clary interrupted smoothly. By now, she'd gathered her wits and wasn't backing out of her decision. She was going to do this. For some time, Jace had been the one protecting her, making sure she wasn't getting hurt. Now it was her turn. Before Jace could interrupt once more, she faced Sebastian, "I swear on the Angel that I'll do whatever you want as long as Jace has no part in this. You will not hurt him, you will not harm him. Deal?"

Sebastian smiled cruelly, "Of course." With that, he extracted the right key from its place on the same rusted ring, and unlocked her shackles. Clary immediately gasped and rubbed at her wrists, wincing as she felt her sore muscles. Then, she was yanked up from her spot on the floor and found Sebastian leading her out of the cell. Jace was still screaming, yelling curses at Sebastian.

"Wait," she pleaded, "Wait. J-Just-What about Jace?"

"Jace?" Sebastian looked bothered that she had addressed him. But as he looked back at the thrashing boy, he smirked. He had a plan. "I might have some…..interesting purpose for him. But enough of that, let's get you to a room."

"Wait, what? You said you wouldn't hurt him!" Clary was frantic, what had she just agreed to?

"Ah yes, but this isn't hurting him. Now, enough! I am done with this topic, and so are you." He leaned closer so that Jace wouldn't hear, breathing into her ear, "You get any little ideas, remember, he means nothing to me. Understand?" Clary nodded. If she didn't do what was told, he would kill Jace without batting an eye. He gripped her arm tighter, and half-dragged her across the stone floor. She turned back to Jace, her eyes wide. Tears threatened to flow, but she held them back. She was done with crying.

Jace was still screaming more mad than ever, and it took all of her will not to break free of Sebastian's grip and sprint towards him. Each of her steps took an enormous amount of effort, like her limbs were filled to the brim with lead. Sebastian dragged her out of the cell and into the hallway, and after a short while, Jace's yells ceased to exist.

They turned a corner and were in a hallway, one filled with countless doors. She wondered what all the rooms were for. He stopped at a particular door, and Clary scrutinized and compared it to the others, trying to find a way to identify it in case she needed the information later. She found no avail. All of the mahogany doors were exactly alike, not a scratch or flaw out of place. He grabbed the set of keys and stuck it in the rusted doorknob.

Flinging the door open, he shoved her into the room, and she landed face-first on a bed. Scrambling to get up, she saw that Sebastian was already halfway out of the door. Looking back at her, he smiled without emotion, pausing in the doorway. "Might as well get comfortable. Don't expect to leave anytime soon," was all he said softly before slamming the door shut, and she heard the click of it being locked from the outside.

Clary craned her neck to look at her surroundings: she was on a plain bed, one with white pillows and blankets, and a simple mirror above a small dresser. There were no windows, and the only source of light she had was a miniscule flickering light bulb on the ceiling above her. Finally, alone, she allowed herself to cry, her face buried in the soft pillows, and fell asleep.

"What do you mean they're gone?!" Simon bellowed. Magnus winced, while Alec and Isabelle were hyperventilating. Maryse and Robert were busy drawing iratzes above their wounds. The Institute stank of demon blood, it being littered everywhere across the floor and walls, which no one paid any attention to.

"I mean they're gone. Zip. Zero. Absolutely no sign of them. Like they vanished off of the face of the Earth. Like they've dis-"

"Okay, okay, I get it," Simon yelled, interrupting Magnus.

He shot a murderous glare in his direction, but Alec wearily put a bloodied arm on his shoulder, silently calming him. He then looked to Simon and said, "I think we can all guess who did this."

"I swear," seethed Isabelle, "I'm going to castrate that little devil and force him to eat himself."

"While I'd love to take that approach," Maryse said softly, a grimace on her face, "We'd need to actually devise a plan before running head first into-Angel, we don't even know where they are."

"Well, might as well start small I guess," drawled Magnus with a sigh, "I'll help you track them." When everyone stared blankly at them, he added sharply, "Go! Find something of theirs I can use! Good God, I'm trying to help you lot here."

With that, everyone rushed about, scrambling to find something with a strong enough connection. Everyone except for Alec, who was still clutching on Magnus's shoulder. Looking up, he smiled faintly, though his eyes were wide with shock, "Thank you," he whispered, "For helping." He leaned up and pecked him on the cheek before heading for Jace's room.

Rubbing the spot where Alec's mouth touched his skin, Magnus muttered, "That boy is going to be the death of me."

Jace was breathing hard, his body drained of energy from all of that screaming and yelling. Clary. He had to get Clary back. She was with Sebastian, doing who knows what. He couldn't let him hurt her. Never. He couldn't stand it if she was gone. Silently, he cursed himself. How could he be so stupid? It was a demon attack inside the Institute. In broad daylight, even. He contemplated ways to try to get out, but when he moved his wrist, his vision doubled for a moment.

Jace looked down and saw it was rubbed raw, dripping with blood, and he noticed that there was a point in the skin where there shouldn't be; he'd broken his wrist. Grunting, he shifted his good arm to try and feel in his pocket for his stele. He came up empty, they'd taken it. Sighing, he leaned back against the cold stone wall, trying to even his breathing.

He heard footsteps echoing loudly down the hall, and looked to his left, through the bars - and saw Sebastian. He growled, a low and masculine sound. "Verlac," he spat, like venom in his mouth, "What have you done with her?"

Sebastian smiled cruelly at him, "I have no idea what you're talking about." He stepped closer until the only thing that was blocking them were the metal bars, "Such a shame, Jace. We never quite got along the first time we met, did we? You seemed to have this sixth sense, and for a moment, I was afraid that you'd known my secret." He broke off with a breathless laugh, "Can you believe it? I was afraid of you, of all people?" Shaking his head, he used his hand to comb back the hair that had fallen into his eyes.

"I'll only ask once more. Where is she?" Jace demanded. His patience was long since worn thin, the width of a strand of thread.

"She is no longer none of your concern-"

"None of my concern?! None?! Are you questioning my unyielding love for your sister?" He noticed that Sebastian had flinched when he'd said that last word, and sneered. "Did I strike a nerve, poor man? Was that word a little too harsh for you? Shall I try 'blood-related'? Or perhaps 'family'? Maybe even 'born-from-the-same-parents'?"

"Enough!" Sebastian roared, clearly agitated about the fact that Jace had found his weakness. He looked him straight in the eye and eerily said, "We are siblings, yes, but that is all the more reason why we are destined to be together. We are alike in so many ways, she is meant to be with me, not some disgusting creature like you."

"You're one to talk. The only correct thing you said was that you were siblings. Clary is nothing like you, a monstrous demon. She is an angel, pure at heart, and you are the devil's curse. Siblings you are, but never compare yourself to her. You say you are alike. That has yet to be a valid statement."

Sebastian, to Jace's surprise, smirked. "Ah, the key word in that sentence being 'yet'."

Jace's eyes darkened violently, and his gaze was sharp. "What do you mean?"

"Ah ah ah," he tutted, clicking his tongue, "It wouldn't be a surprise if I told you, now would it? And I like surprises. Don't you?"

"You vile bastard."

"No? Not a fan of surprises? Oh well, I guess some people are haters." After a moment of pretending to be lost in thoughts, debating about his choice, he said smoothly, "All right, fine, fine, I'll tell you." His look was one of outright glee and pride; he thought his plan was going to work. "You remember, as you've said before, Clary has yet to become like me. Has yet to "come to the dark side," if you will. I'm sure demon blood would change that."

Jace's eyes widened in realization, and he spoke slowly, his anger audible in every syllable he spoke, "You're going to inject her with demon blood."

Sebastian smiled coldly, "Yes, but not just her, her child as well."

Jace almost hurled right then and there. The little fucker was planning to impregnate her. He was planning to turn another innocent child into another one of him. "Like hell you are."

Raising an eyebrow, Sebastian questioned, "Oh really? Do you really think that you have the power to counter my actions? Anyways, it won't really matter in a while. You'll be long gone when this happens."

He was also planning to kill him. Wonderful, he thought joyously to his self, Not only is he trying to create more of him, but I'm on his bucket list of people to kill too. Though, being his snarky self he didn't let his emotions show. His heart was hammering inside of his chest, but his outer demeanor didn't let it crack. Instead, he laughed sharply, surprising the both of them. "Do you really think that you can get away from this?-"

"The Clave will never find me," he said carefully.

"I wasn't talking about the Clave, I was talking about Clary. Do you really think that you can do this to her? That she will allow you to manipulate her? She is the most stubborn and hard-headed girl that I know, and I think you'd rather have your manhood rid of than face her."

Sebastian tilted his head to the side thoughtfully. "But isn't that why I have you?"

Dread unfurled in the pit of Jace's stomach. She was the most stubborn and hard-headed person that he knew. Clary would definitely go through all of that torture just for the sake of him. He'd just proved his own point.

Smiling faintly, seeing that he won this round, he started to back away slowly. "See you soon, Jace. Keep that happy thought in mind. Sleep well, don't let the demons bite. Literally." After snapping his fingers, he walked away, his strides echoing loudly within the hall. Literally? A snarl came from the corner of the cell, and Jace looked to see that two demons emerged from the shadows, snarling and growling. He cursed. Literally.

Oh ho ho, so what'd you think? Too much? Too little action? And before you kill me, no the demons will not fatally injure Jace. Again, sorry for the late update. I'll try to post more often, if I can stop procrastinating. Anyways, thanks for reading! Please review!