Author's Note: So today I watched this movie about a world where people get TiMERs implanted in their wrist that tell them how long it is until they meet their soulmate, their "One". This is my Shadowhunters take on it, but I think it makes sense even without knowing the original source. Exactly 800 words because I'm weird like that. 🙂
Alec's first reaction to Jace is canon, thanks to CC's Son of the Dawn.
***
Like most Shadowhunters, Alec got his TiMER installed during his first rune ceremony. A few months later he first laid eyes on Jace Wayland.
"Wow..." he whispered, immediately wishing he could take it back, because next to him Izzy started giggling. Still, he surreptitiously snuck a glance at the countdown on his wrist, only to deflate when he saw that it still hadn't started. Whoever his soulmate was, he or she - although Alec secretly was pretty sure it would be a he - did not have a TiMER of their own. Neither did Jace, as Alec noticed with a hidden thrill when the new arrival offered him his hand to shake, but he quickly suppressed the thought, not wanting to get his hopes up. Of course the coolest guy he'd ever met wouldn't be his soulmate.
Unfortunately it only got harder for Alec to keep that stubborn little voice in check the better he got to know Jace. There was something fragile and vulnerable hiding underneath that golden exterior, something no one except Alec got to see for some unfathomable reason. No one else in the world knew why Jace didn't have a TiMER, but Jace told Alec of his father's disdain for love late one night, after Alec found him hiding on the roof. Pulling him into a tight hug, Alec promised impulsively, "Well, you'll always have me."
"Will I, though?" The darkness made it impossible for Alec to make out Jace's features, but he was pretty sure he didn't imagine the feather-light touch of fingers against his wrist, right where his TiMER lay dormant, waiting for the moment when it would begin counting down towards the moment Alec would meet his soulmate. And for the first time Alec found himself not looking forward to that instance. He did not want a soulmate if that wasn't Jace, and the thought hit him like Hodge with a training staff, but before he could form any words, Jace slipped out of his grasp. "Good night, Alec. Thanks for listening - I'll see you tomorrow."
With that he disappeared into the Institute, leaving Alec feeling as if he'd just missed something important. He might be the person who knew Jace Wayland best, but there were still times when Jace very much kept his own counsel. Sighing, Alec went back inside, hesitating in front of Jace's door, before shaking himself slightly and continuing to his room. He spent most of the next day wondering whether that had been a mistake, because there was no sign of Jace at breakfast nor during training, and no one seemed to know where he had gotten to. When he still hadn't shown up at lunch, Alec went so far as to check the security footage, only to discover that Jace had slipped out at the crack of dawn.
As the afternoon wore on, Alec had trouble focusing on Hodge's lessons, wondering where Jace had gone - until all thoughts of Jace were suddenly wiped from his mind as his arm began to beep. Alec's arrow completely missed the target, and Izzy squealed, "Alec, it's happening! Your soulmate finally got his TiMER installed!"
Lowering his bow slowly, Alec found himself strangely reluctant to actually check the countdown. Finally he looked down, only to shake his wrist in confusion at the sight of a blinking line of zeroes.
How was that possible? He exchanged a stunned look with Izzy, trying to wrap his mind around the fact that he'd already met his soulmate.
"Alec?" Whipping his head around, Alec saw Jace hovering in the doorway, looking uncharacteristically hesitant. He was cradling his wrist, and Alec's breath caught. He barely noticed Izzy pulling Hodge out of the room through the side-door, because Jace was walking up to him, hand outstretched like an offering. "Please tell me that yours zeroed out, too, because otherwise I'm going to feel like a complete asshole."
"You are an asshole," Alec laughed, disbelieving joy bubbling up inside him as he closed the remaining distance between them and presented his TiMER to Jace. "But yes, it did, and I was so fucking scared that it wouldn't be you."
"I needed to make sure, because no matter what my father said, I can't believe that loving you makes me weak." Reaching out, Jace trailed a finger reverently over the line of zeroes, a shiver racing down Alec's spine. "Alec Lightwood, will you be my parabatai?"
Only soulmates could become parabatai, but not all chose to. Alec, however, didn't hesitate. Tangling his fingers with Jace's, he pulled him closer until their foreheads rested together, words caught in his throat. He didn't need them, anyhow, because a smile like the sunrise lit up Jace's face.
Warmth blossoming inside him, Alec pressed his lips to his soulmate's, tasting their future on his tongue.
