A/N: Hey everyone, I know it's been a while since I updated, but I have finally finished my other story (merge) and so now Revelations will be my number one priority.

"He was my son." She said.

Jace stared at the warlock girl in confusion, no… in awe, no… wait what?, "You mean, you adopted him?" He asked, already guessing the answer. His guess was right; Tessa shook her head. "I gave birth to him." She said, "Just like I gave birth to his sister Lucie, who later became Lucie Blackthorn." Jace didn't know what to say, "H-how?" He asked. Jace Herondale was not usually one to be at a loss for words, but if Tessa was telling the truth, it meant that they were related. Jace had never been related to anyone before.

For her part, Tessa seemed like she was just as uncomfortable as he was. She moved awkwardly over to the other side of the couch and motioned for Jace to join her. He could hear the low voices of his friends and family and the other room and he wondered if he should just ignore the strange, probably sleep deprived, warlock and go back to them. But he didn't do it. He looked at Tessa, who was watching him carefully. She certainly seemed sane, and she had been the one to save Alec's life. He decided to hear her out. He sat down next to her, and nodded, indicating that he wanted to hear her story. Tessa took a deep breath and started.

"A long time ago, back in the 19th century, before the accords were signed, the Warlock John Shade and his wife were killed by a group of Shadowhunters, lead by Aloysius Starkweather." Tessa glanced up at Jace, to make sure he was listening before continuing, "What the Shadowhunters didn't know, or didn't care about, was that the Shades had an adopted son. He tried to complain to the Clave about the murder of his parents, but predictably they ignored him. So he vowed revenge." Tessa winced slightly, and Jace found himself leaning forward, he didn't understand what this story had to do with anything, but it was still seemed like it would be really interesting. "I do not know what the Shades named their son," Said Tessa, "But after they died he renamed himself Axel Mortmain."

"Hand of death." Jace translated, Tessa nodded, "He wanted to spite the Nephilim by calling himself something that would sound like a Shadowhunter name. However, he did not attack the Clave directly, he was much to smart for that." She said it bitterly, "Axel Mortmain founded the Pandemonium club." Said Tessa, like it was the most disgusting thing he could have done. "Pandemonium- like the night club?" Asked Jace. "The organization has changed greatly in the past one hundred years." She replied, "When I was young it was a group that mundanes could join in order to have the opportunity to gamble with downworlders and learn about their powers. It was also the front for a terrorist organization of demons and downworlders whose soul goal was to exterminate the race of Shadowhunters."

Jace stared at her in open-mouthed horror. Tessa laughed a little, "Don't worry, they didn't succeed. Obviously. But they came pretty close." Jace closed his mouth, aware that in the past five minutes he had done more idiotic things then he usually let him self do in the space of a year. Clary, occasionally Alec, and very occasionally Isabelle, were the only people that he usually let see him vulnerable, but Tessa's piercing grey eyes and blunt manner of speaking, made it near impossible to act tough.

"Mortmain wanted to create an army of indestructible automatons, powered by the souls of demons." Said Tessa, as if it were a perfectly normal goal.

Jace went back to gaping.

"He was able to invent some automatons that could follow orders, and were great fighters, but in order to infuse the demon souls into them he needed a formula that his father had created."

"But his father was dead." Said Jace, "Yes, his father was dead." Agreed Tessa, "So Mortmain came up with a plan that would allow him to both communicate with his father, and get revenge on Aloysius Starkweather. He created a creature that could not only change their form, but access their memories, even after they died."

"You." Said Jace. Tessa nodded again, "There are many Warlocks and Faeries who can shape shift, but none of them can do what I do. Because I am not a warlock."

"But you said-" Jace began, but Tessa cut him off, "I call myself a warlock, because that is the closest approximation of what I am, but in truth I am really my own unique species. At some one point Magnus tried calling me a "warlephlim", but it didn't really catch on. See, warlocks are generally understood to be the offspring of a demon and a mundane, but my mother was, in fact, a shadowhunter, and since Nephilim blood is dominant, many people (the silent brothers included) would not call me a Warlock, but a Shadowhunter."

"But that's impossible." Said Jace. "Is it?" Asked Tessa, "Why?"

"Because the children of shadowhunters and demons are always stillborn."

"Why?"

"Because our runes protect us."

"And all shadowhunters have runes?"

"Yes. Obviously."

"What about Clary?" Jace blanched. She was right, Clary hadn't received her first rune until the day that they had met, "You mean Clary could have been- a demon could have-" Jace couldn't bring himself to say the words, they too awful to contemplate.

"Don't worry." Said Tessa, "When Jocelyn first came to me and Magnus, we warned her about what had happened to my mother and we convinced her to let us put a protection spell on her, to protect her from demons. I only used Clary as a theoretical exception to the rule." Jace let out a relieved breath. "You may have noticed," Tessa continued, "That the Seelie Queen does not particularly approve of shadowhunters." Jace nodded. "Well, she did approve of Mortmain's plan to destroy them, so when Alonyus Starkweather had a grand daughter, she agreed to switch the Nephilim baby with a sickly mundane one. The poor human girl died when she was given her first rune, and Adele Starkweather grew up to be Elizabeth Gray; my mother.

"After she got married, Mortmain sent her a demon, in the form of her husband, and you can guess what happened next." She was right, Jace knew exactly what had happened. "My parents died when I was three. I was raised by my aunt who died when I sixteen. After she died, I moved to England, where I was immediately kidnapped and shown how to use my powers. They used to whip me until I changed my form." Jace felt a rush of sympathy. He had been raised by Valentine; he knew what it was like to be mercilessly trained for a specific purpose.

But surprisingly, Tessa's eyes had become dreamy when she started talking about her capture, "I was nearly at the end of my rope." She said, "But then… At just the right moment, I was rescued by a handsome stranger." She giggled, "It was a bit cliché, I have to admit."

"Who was he?" Jace asked, though, again, he already guessed the answer.

"He was William Herrondale."