Percy eyed Annabeth as they left the shop. Something was up with her. She obviously had a history with these people-one she didn't want to share. Annabeth wasn't very fond of memory lane in general, but this was different. It felt like she was purposefully hiding something from him.

Annabeth sighed and sat down on a bench just outside a frozen yogurt shop. Percy joined her. "What happened?" Percy asked a second later. He expected Annabeth to brush it off like she had every other time, but when she opened her mouth no lies came out.

"You know what those people are, right?" Annabeth asked, "Their Shadowhunters. Nephilim. They hunt demons. Things that they think shouldn't exist."

"And?"

Annabeth sighed. "I met Isabelle before I met Thalia and Luke, and it wasn't under the best circumstances."

Nine Years Earlier

It was raining. The rain splattered on the ground as a small pair of tennis shoes hit the pavement, running from something horrible.

Annabeth didn't know how to describe it. The thing that was chasing her was not like the other monsters she'd fought. This one spit black goo everywhere. Black acid goo. A little bit had landed in the young girl's hair and the part it touched had disintegrated. If the thing got near Annabeth again...she shuddered to think of what would happen. Instead, she kept running.

She took a left, and then a right, and then another right, and then a left, until she was almost sure that she had lost it. Annabeth leaned against the brick wall in the alleyway. When she had run away from home, she hadn't expected monsters. Then again, Annabeth wasn't sure what she had expected.

Annabeth was different, this much she knew. She was smarted than most of the kids in her class, despite the fact that she was dyslexic. And she could read Greek. Annabeth had discovered this quite by accident while she was at the local library, but that was before. Before she'd run away, and monsters had started chasing her.

Annabeth let out a sigh of relief just as the monster that had been chasing her burst through the door to her left. She dodged to the side, nearly missing it's spiky black tail as it retreated away from Annabeth and the door beside her. A second later, a small figure jumped down from the roof above and stabbed it with a glowing knife. Annabeth watched in awe as the monster began to fold in on itself until it disappeared with a crack.

The figure wiped monster guts of of herself, and Annabeth realized that she was a girl around her age. She was wearing all black, with her black hair pulled back in a ponytail. It made her blue eyes stand out. Tattoos littered her skin-strange symbols that Annabeth didn't recognize. She grinned at her, then started walking away.

Annabeth snapped into action. She didn't know who that girl was, but she had just defeated a monster as if it were as simple as cleaning a toilet. "Wait," Annabeth said.

The girl froze and turned around, looking at Annabeth quizzically. "Are you talking to me?" she asked.

"Of course I'm talking to you," Annabeth said, taking a step closer to the girl, "Who else would I be talking to?"

The girl seemed to ponder the question for a moment, but didn't seem to find a reasonable answer. "But, you can see me?" the girl said as more as a question than as a fact.

"Duh," Annabeth said, "Why wouldn't I be able to see you?"

"Because you're a Mundane."

Annabeth's eyebrows shot up. "I'm not mundane."

The girl rolled her eyes. "Not mundane, a Mundane. You know, human."

"Human?"

"Yeah," the girl said, "human."

Annabeth shook her head. "I'm not human," she said. She had no idea why she was telling the girl this. She could be a monster, some form of creature higher up on the food chain than the monster she'd killed.

"You're not human?" the girl asked, "Then what are you? A warlock?"

"A warlock?"

"Yeah, like the offspring of humans and demons."

Annabeth considered this for a moment. It would explain some things, like how she didn't have a mother, but it wouldn't explain why she could read Greek or was dyslexic. "What do warlocks do?"

The girl shrugged. "You know...warlock-y stuff. They have a mark. If your a warlock, you have a mark."

"What's it look like?"

"Like wings, or cat eyes, or something. Something noticeable. Like green skin. Do you have one of those?"

Annabeth shook her head. "No," she said, "I'm not a monster. I think I might be a monster hunter, like you."

"I'm not a monster hunter," the girl said.

"You're not?"

"Of course not. I'm a Shadowhunter."

"What's a Shadowhunter?"

The girl paused. "It's a demon hunter."

"Isn't that just a monster hunter?" Annabeth asked.

"No," the girl stomped her foot in a puddle, "It's different."

She seemed angry, so Annabeth didn't press the issue. The girl stared at her for a moment before speaking again. "You're probably just a Mundane with the sight. Go home."

"I can't," Annabeth said.

"Why not?"

"I don't have a home."

"How come?" the girl asked.

Annabeth shrugged. "I just don't."

The girl nodded. "Okay," she said, "You can come with me for now. Then you have to leave." Annabeth grinned and followed the girl as she began walking out of the alley.

"I'm Annabeth, by the way," Annabeth said, "Annabeth Chase,"

The girl glanced at her then smiled. "Nice to meet you, Annabeth Chase. I'm Isabelle Lightwood."