A/N: Co-writing fanfiction with @marauder-level-chaos is here!! It's a Marauders and Shadowhunters crossover fanfic, featuring our OCs, Amethyst "Meth" Black and Aster Hightower. First chapter takes places during the second episode of the first season of Shadowhunters, hope you enjoy it and feedback is always welcome! (anyone who wants to be added to the tagslist let us know)

Chapter 1: Godammit

This was ridiculous. Actually, missions for the whole week had been ridiculous. The best and brightest shadowhunters of the New York Institute were stuck babysitting a little girl, all for Jace’s desperate need to get laid. Okay, that last bit may be a slight projection on Alec’s part. Still, ever since this Clary had entered their lives, nothing seemed to be going as it should. Even now they were at the City of Bones, waiting to get her memories back. This girl was definitely way more trouble than she was worth. She had lived her life as a mundane for 18 years and nobody but Alec seemed to think that was suspicious. Jace seemed to trust her blindly and Alec had no idea why. Even Izzy had bonded with Clary’s mundane friend. Maybe if he tried he could get used to these new additions to the institute, but frankly, he didn’t want to. He excused himself from the group under the guise of minding the perimeter for any unwanted guests. There was only one person Alec knew would agree with him about this situation. He picked up his phone and quickly dialed Amethyst, his best friend halfway across the world. It only rang twice before she picked up.

“How’s it going, hot stuff?” Her voice was heavy. Alec could tell he’d woken her up. But he also really needed to talk to her.

“Jace brought mundanes into the Institute. Well one mundane, and a long lost shadowhunter, Clary Fairchild. Her memory has been wiped.”

“Fairchild. Where have I heard that name before? I think I heard my parents talking about it. Anyway, why does she bother you so much?’

“She doesn’t bother me, Meth. I don’t even know her. I just can’t trust her.”

“Hmm, but Jace can. That’s what’s bothering you, isn’t it?”

“You know, I really thought you’d be on my side with this.”

“And I am! I’m just saying there’s more to this than you’re telling me.” Alec knew she was right. Well, partially anyway. “Oh come on, don’t fucking sulk. You’re just pissed because I called you out about Jace. You know I’m always here to talk about it.”

Alec rolled his eyes. “No thank you. I don’t need your leftovers.”

“Good cause it’s not that good anyway.” Their conversation was cut off quickly when Izzy returned, slightly out of breath.

“I lost Simon.”

“Look, Izzy, the mundane isn’t really my responsibili-”

“To Camille.” Meth must have heard that because Alec heard her sigh into the phone.

“Never a dull moment with the Lightwoods.” It was as if on cue, Jace and Clary made their way out from seeing the Silent Brothers. The shocked looks on their faces indicated a strong lack of good news.

“Who’s Alec talking to?”

“Amethyst.”

“Oooo, tell her I miss her.”

“Oooo, keep it in your pants, Wayland.” Meth hissed in Alec’s ear.

“I’m pretty sure she heard you. Anyway, what did you find out?”

Jace and Clary exchanged a look that made Alec want to barf. Why couldn’t they just get to the point?

“Her father is Valentine.” Alec stood there, a blank expression on his face, fighting the urge to scream “I told you so.” Amethyst, however, had no such reservations.

“WHAT?! And she’s still alive?! This is why Alec is the only one in this group with half a brain cell.” While Alec had no doubt that Meth’s screaming had ripped his ear drum, he wasn’t disagreeing with her. Clary should not be here right now. The correct thing to do would be to turn her over to the Clave. They would know what to do. A few 20-something Shadowhunters are not equipped to handle a situation like this.

The ride home was as awkward as Alec had imagined it would be. Neither Jace nor Clary would look at him. And he couldn’t bear to look at them either. How did one little girl make their lives so complicated? Immediately, he went into the training room at the institute. It usually helped him clear his mind.

“Easy there, tiger. You don’t want to break that open.” Alec immediately knew whose voice that was. He’d recognize that insufferable British accent anywhere. Sure enough, he turned around and Amethyst was right there.

“Oh thank Raziel. These idiots are driving me insane.”

“I know. That’s why I asked Fell to portal me here. And I brought Reg. Sirius is on a mission and I’m not leaving him alone in that house. Now, let’s talk over coffee?” Alec nodded, more than willing to catch her up to speed on the shit show that had become his life. And all for a girl he didn’t even know.

She loved the Shadow Market! So many colors, sounds and smells for her to enjoy, always something new to discover. Free to mingle, to walk around at her heart's desire, to observe. Tonight she was even lucky, having spotted several mundies with the Sight! She could distinguish them from a mile away; there was something very characteristic in their scent, in how they looked around in confusion and wonder alike, in how they hesitated to stop at a stall and ask for, well, anything.

Funny, she chuckled to herself. Three hundred years and she was still amazed by something as trivial as the excitement of the mundanes.

She shook her head, focusing back on the stunning stand of masks in front of her. All sorts of colors here too, adorned with breathtaking gems and reminding her of a time when the world was younger and she twirled in elegant ballrooms wearing gowns and flowers in her hair. Perhaps the mask with the sapphires would make a nice addition to her collection? Or the other one, the silver, with the powerful glamour?

Suddenly, a gentle vibration from her jacket pocket brought her out of her thoughts. With a frustrated groan she picked up her cell phone, eyes widening at the caller's ID.

“You've got to be kidding me!” She whispered before quickly answering the phone. “On a scale from one to ten, how messed up is it?”

“Now, now, is that any way to greet an old friend?”

“Didn't know you belonged in this category, Raphael.”

“Charming, florcita, but for once I need you to just listen. It's time you leave your little London nest.”

"And why would I do that?”

“Camille is breaking the Accords, does this sound like a valid reason?”

“She what?” Aster left a hiss at the disgustingly familiar name, which was a harbinger of bad news especially when followed by the statement breaking the Accords.

“I know for a fact that your hearing is perfect, my dear. She ordered us to capture a mundane. Hopes to get the Mortal Cup that way.”

“Raphael, stop stalling already! Spit it out, what else is going on? How will a mundane grant her the Mortal Cup?”

“Because he is friends with the Fairchild girl.”

Fairchild?

Did Raphael just mention the Fairchild girl?

The Fairchild girl Magnus told her about all these years ago?

And Camille wanted her mundane friend?

Were these idiots actually trying to start a war that would likely blow up New York?

“Raphael Santiago, what have you done?” A snarl marked Aster's face, making her fangs visible for a few seconds.

“Let's see, I risked my neck by calling you? I try to protect my kin? Now the choice is yours. Clary Fairchild and her little Shadowhunter friends will attempt to save their mundie. We could use an envoy, dare I say, even an ally.”

While Raphael kept talking, part of Aster still tried to process everything she just heard. Not that Camille's breaking the Accords should be particularly shocking. Leave it to her to still be a huge pain even centuries later!

Her eyes involuntarily traveled to the alluring night sky, filled with countless stars. Dawn was a couple of hours away. If she were quick, she'd be on time.

And then the small business of entering the New York Institute.

Who said that life at three hundred would be boring?

Tagslist: @quickbright