Title: City of Veiled Shadows

Summary: With Sebastian still on the loose, the Clave are desperate for a way to end him and the hell he is about to bring. And Sebastian is desperate for a way to make sure he has the upper hand. A girl, Nadia Ravensblood, might just be the key both are looking for. Nadia has been hidden well all her life but now her secrets will come to light and in the wrong hands could be deadly. Set after COLS.

A/N: While I'm anxiously waiting for the release of COHF, I decided to go ahead and start writing this idea that has been bothering me for quite some time. I'm still cracking down on all the details and making sure I get all the characters right so updates might be sort of slow at first but I will try to speed them up. This story will focus both on our favorite characters and on Nadia.

Disclaimer: I don't own TMI or any of its characters.

Prologue

The forest was unearthly quiet. No sounds of leaves swaying in the wind, no crickets or birds, no animals roaming around; Sebastian knew something was off the second he stepped into the dark woods and all noise seemed to vanish as if he were in a bubble. It wasn't natural even to him. Then again this wasn't a natural place. He glanced around, only seeing the moon in the sky and the trees around him. His hands curled around the sword at his waist instinctively.

With the way things were, he could never be too careful.

He continued walking, following the dirt path under his feet. Nothing seemed to be alive in the forest It wasn't until a few more minutes of walking that he came upon the person he had come here for. Leaning against a tree, she looked beautiful, with her long blonde hair and slim-fitted dress that showed her figure wonderfully. A small smile graced her lips as she watched him come closer.

"You did come," she said with a touch of amazement. Her voice was noticeably weak but it still held a hint of the strong person she once was.

Sebastian kept his grip on his sword but relaxed slightly. "Of course I came. I don't back out of my deals. Now you said you have information for me?"

The woman unhitched herself from the tree and nodded. Standing at her full height, she was most definitely tall. Her eyes were a dark red and there was something in her face and stance that seemed off, as if she was in pain. "But first, what you promised me." She stared at his neck, where the demon blood in him pulsed. The expression she wore reminded him of the vampires who hadn't eaten in days.

Sebastian swallowed back his annoyance. "Fine," he said. "Take my blood."

The Dark Shadowhunter tilted his head to reveal his throat and in an instant the woman had her teeth in his skin. It was a weird feeling, the sudden weight grasping him by the shoulders and the pinch of something sharp on his neck. She let out a moan while he tried to manage to stay calm. A dizzy sensation came over him at the loss of blood as the woman continued to drink more and more. Eventually she released him and stepped back, wiping her mouth with the back of her hand.

"I feel much better now," said the woman, "More powerful."

And she looked it. The red in her eyes shown with more fierceness, a sort of glow seemed to surround her, and the way she held herself was more confident and comfortable. She looked deadly and dangerous. His blood had transformed her into the person she had been before her downfall. It had turned her into a weapon Sebastian could use to win his war. If all it took was for him to give up some of his blood every now and then, he was willing to pay the price. Winning was all that mattered. He already lost his connection to Jace; he needed something to be a step ahead of the others.

A war was coming. Sebastian had no doubt about that. His dear sister and her friends were probably trying a way to stop him this very instant, but he wasn't the least bit concern. With this creature and the information she would provide, the Shadowhunters were going to be taken by surprise. A storm was going to come up and sweep them away before they even had a chance to draw their swords.

"Now tell me what you know," he told the woman.

The woman clasped her hands together to form a ball and in the center a circle of light appeared. The brightness almost blinded him and he had to look away until it dimmed down. In the middle of the light was the face of a young girl, with dark brown hair and gray eyes. She was laughing at something he couldn't see, the youthfulness evident in her face making her some much more different than the woman in front of him who he imagined had lived many years longer than she showed.

"Her name," the woman began, "is Nadia. The powers she possesses are something no Shadowhunter has ever seen before. She's able to control demons to the point where they can be nothing but mere pets to her and when she does, she can transfer demon poison into her to kill the people around her with simple skin to skin contact. It's as if she becomes one with demons, able to become just as much a monster as they are. She is strong, almost as strong as you. But her parents have hidden her well."

"How'd you find out about her?" asked Sebastian.

"I have my ways. Your father experimented on more people than just you. He came to me, the day before the Mortal War, and asked me to keep an eye on her. And I have." The woman laughed softly. "It's been quite fun watching teenage drama. All the tears and yelling at her parents, all the boy problems she runs into."

Sebastian crossed his arms and leaned against the trunk of a tree. His patience was beginning to wear thin. He wasn't here to listen to the woman explain every useless thing. He only wanted the news that would help him. "Tell me where she is and how I can get my hands on her. And when I do, I'll come back for you and get you out of this…place you call a home and bring you back to mine. How does that sound?"

The woman's eyes widened, surprise written all over her face. The ball of light in her hands extinguished and she nodded fervently. "You would do that? I've been stuck here for years, not able to get out and see the world for myself. It's a wonder I've managed to stay sane."

"All you have to do is help me find the girl, and then give me the name of who created this prison. And then when that person is dead, you'll be free to come with me and we'll both get our revenge."

She was excited, he could tell. He was on the right track of becoming more likable than his father. It was too easy to see that his father never bothered to lend out a helping hand to her, even though he could have made the difference between winning and losing. Maybe that was why he wasn't here today.

Sebastian wouldn't make that mistake.

"I'll tell you everything. Just remember, be careful when you find her. She will need persuasion to fight on this side. Say the wrong thing and she will just as quick become your enemy," the woman warned.

"I'll win her over," said Sebastian, "trust me. Now where is she?"

He was ready to get the last piece of the puzzle, the pawn he could count on to bring him ahead in this war. He was ready to see the bloodshed, to hear the screams, to feel the pain. He was ready to win.