A/N: So, I've been a fan of this series for years, but this is the first time I have actually published a fic for this fandom so yeah. Yay for me! I guess this is kinda AU, set during COLS. I hope you like it, please read and review.

Disclaimer: Boy, would I love to be Cassie.

Enjoy :)

Blue Eyes and Memories

The first time Tessa saw Alec Lightwood, her heart stopped.

"Will?" she had breathed, pain and longing lacing her voice as she said so, "Will, is that you?"

It was the eyes, she figured, those blue, piercing eyes that she hadn't seen in years. She had almost forgotten how bright the violet of his pupils had been, and her memory did not even come close to doing the true colour justice. Gosh those eyes, she had fallen in love with a boy who had those eyes, and when she met another boy with those eyes it almost killed her.

But this wasn't her boy, despite those haunting eyes this boy wasn't the one she had fallen in love with.

This became clear as the boy -not her boy, never her boy she must remember- furrowed her brows at her and answered, "What?"

Tessa stepped back, recoiling almost in realization. No, this wasn't Will. His voice was not the same, there was no playful lilt or British accent. This boy was thinner than hers had been, and his black hair did not fall away into his startling eyes.

A girl stepped up then, standing beside the boy, her eyes -though darker, more black than blue but it was still those eyes, those same burning blue eyes- flaring up protectively, "Who are you?" she questioned, and it was posed in such a demanding way that hurt Tessa even more. This girl was much like another girl she had once known, who was strong and fierce and has those bright blue eyes. "What do you want with Alec?" the girl continued loudly, snapping Tessa out of her painful nostalgia. So the boy's name was Alec. This was not Will, not it never had been. The girl wasn't finished, "And who in the Angel's name is this Will we keep hearing about?"

Tessa stepped back further, away from the pain that was this blue-eyed pair of siblings and closer to Magnus who had been just behind her. Because out of all people, Magnus knew. He knew of the pain of loss and heartbreak. He knew what Tessa was feeling and he could bare it, but sometimes she just couldn't.

She shouldn't have come. She had known the moment the idea was posed that she shouldn't go. Tessa had spent years avoiding Institutes ever since she left London. Avoiding the pain of not having Sophie cleaning the halls, or Charlotte running the place. Staying away from Shadowhunters and the lovely but painful memories -of two wonderful boys whom she had once loved- that they brought. But this was Magnus, and over all these years Magnus had come when she asked so she figured she owed him a favour. She owed him so many favors that she would probably never get to repay because the sight of this boy was killing her right now, but she still had come.

Tessa looked up at Magnus, her eyes swimming with a lifetime of pain and unanswered questions, "Magnus, who is this boy?" she asked desperately.

Magnus looked down at Tessa, his expression unreadable, "This," he said, gesturing to the boy without moving his gaze from Tessa, "Is Alec Lightwood, and his sister Isabelle."

Lightwood. Of course, it all made sense now. The eyes weren't Will's -oh but they were, though it was easier to deny it- they were Cecily's. Though, the thought of that hurt too. Tessa nodded, "Yes, Lightwood." she said in a hushed tone, resisting the overwhelming urge she felt to reach forwards and softly touch the boy's cheek. Tessa's fist curled at her side -no, this wasn't Will. Never Will.

She turned back to the Lightwood siblings, when a flash of red on Isabelle caught her eye. A pendant hang loosely around her neck, bright red and glowing as Tessa stepped towards it. She knew that pendant, had seen it many times in her early years. Without thinking, she moved forwards and picked it up of Isabelle's chest, holding it softly in her hand as she ran her fingers over the smooth stone, "Oh, gosh." she breathed sadly.

"Hello?" Isabelle snapped Tessa out of her thoughs again as the younger girl jerked back, pulling herself and the pendant away, "Would someone like to explain what is going on here?"

Tessa almost laughed, and probably would've had she not been so sad, "Cecily." she whispered, and there was a hint of a smile on her face now.

Isabelle placed her hands firmly on her hips, and opened her mouth to speak but Alec cut in and said instead, "Magnus? What is happening here?" he asked.

Magnus stepped forwards, "This is my friend, Tessa Grey." he introduced, and by the look on Alec's face she figured that that wasn't what he ha meant when he asked, "She is here to help."

"How can she help us?" asked Isabelle, hands on her hips.

"Tessa has a special gift," the warlock explained, "that I believe will help I find your brother."

Another Lightwood, Tessa thought, and she couldn't help but wonder what this one would look like.

"Really?" Izzy looked hopeful, "You can help us find him?"

Tessa nodded, "Yes." she said, taking up a business-like air in her tone, "And who is this boy we wish to find?"

"Jace." Isabelle said in a desperate way that made it clear she loved this boy as much as she loved Alec.

But it was Magnus Tessa looked at, who had said that same name at the same time but in such a different way. The tone of his voice was almost painful to hear and it made her furrow her brows in question. "Jace," began the warlock, "Jace Herondale."

There was a sharp intake of breath as Tessa visably recoiled, almost folding into herself as if she had been punch in the gut. That meant almost certainly that this boy was a descendent of hers. Of hers and Will, and that killed.

She had barley survived seeing these Lightwood siblings, but have to face a Herondale, a Herondale that she could already see in her mind's eye. A Herondale that almost certainly had the same smirk her husband had used so well.

Isabelle seemed to ignore her reaction, "Can you find him?" she asked, voice ringing with hope and pain. The need to find this boy.

Yes, Tessa would find him, because this boy was probably all she had left. Because even if it broke her heart she couldn't let the Herondale name just fizzle out like that. Not without a fight, "Yes." Tessa nodded, trying to keep her voice steady. She placed her hands on her hips and set her jaw, grey eyes steely, "I will help you to find him. Where do we start?"