Isabelle has always blazed into his life. He cannot remember a time when she hasn't exploded into his eyesight, except, perhaps ironically, the very first time they met. She was simply cooking in the Institute's kitchen – and at that point, he'd actually been willing to eat whatever she made, he'd since learnt better – and lecturing Jace. It was funny; to think they had started out so quietly.

Today, however, was no different from the usual. Isabelle had let herself in. He was startled to look up at her – she appeared to be smiling, but below that, he could see the shakiness in her hands, the tightness of her eyes. "What's wrong?" Simon asked, cautiously. He feared it was unlikely he'd want to hear the answer.

"Magnus and Alec," Isabelle replied. Simon was alarmed; now it seemed as though she was holding back tears. He adored Isabelle, really, he did, but a crying girl was a crying girl. "They broke up." She raised her head, nodding at him. "They broke up," she repeated, in a tone without any insinuations, or indeed, inflection. "Because there's an eternity between them."

And it hit him, what she was saying. He'd thought about it before, how could he not? Yet, somehow, he'd never put it to Izzy. He'd never thought that she and he would be affected by it. Or maybe he had, and he simply hadn't wanted to be the first to say it out loud. He remembered drinking her blood, the delicious sweetness she had – it went right along with her infectious laugh, those eyes so determined and piercing. Isabelle always saw right through him. Most days he wanted her to.

Most days. He eyed her worriedly as she gave a bitter snort, "Who would have thought you'd be the one to leave me behind?" Simon knew not to be offended. Isabelle was blunt, just as she was beautiful. Her barbs couldn't sting if he didn't let them. He knew she was only scared. He longed to wrap his arms around her, but for some inexplicable reason, he couldn't make himself move. "You will, though. You'll be young forever, you'll want adventure and freedom and… and beauty that never fades." Isabelle looked down again, and he could see the tears clinging to her long lashes this time. It was a sore spot with Isabelle, he knew… this insecurity. It came from her scars, her killing scars. He couldn't imagine any reason he wouldn't find her beautiful. He would always see her as beautiful.

Simon found his feet. He traced a long white zigzag on her right arm, and reached for her hand. "Isabelle," he began, only to find her finger on his lips and her glare like thunder. He quietened immediately. He was no coward, but as sweet as she could look, Isabelle Lightwood was the deadliest angel he'd ever encountered.

"Don't start, Lewis," she growled. He almost smirked, as un-Simon-like as it felt, and wondered what she would do if he licked her finger. Somehow he thought she might not be prepared for that sort of tactic. All the superhuman training in the world couldn't compare to middle school warfare. Of course, he couldn't guarantee he wouldn't then suck into the rest of her delicate skin. Perhaps he had better not. "I don't want to hear any of your stuttering. This is how it's going to be." He nodded along with a charming smile, knowing that arguing was futile. "You will not be breaking up with me. You will not be finding some pretty little blonde vampire that can keep up with you over the years. Because, trust me, if I find you cheating on me, and I will find out, I won't have any problem breaking the Accords to show her who you belong to. You hear me?" Isabelle said it with her usual fierceness, that tough nitty-gritty Shadowhunter attitude that equally enthralled and irritated him.

Simon knew his eyes had softened as she rolled her own. Sometimes he had to wonder if she really was as constantly exasperated with him as she appeared. "There's no one I want more than you, Iz," he shrugged. It was the truth. "Never will be." For one thing, he really might need that smile of hers to survive.

Simon knew the fear bubbling up inside him couldn't be ignored. Life without any of those he loved was an unbearable thought. But, perhaps, it could be for another day. He took a double-take, "Wait, Alec and Magnus split up?" He gave her a look of mock-horror, "But Magnus was going to let me borrow his lederhosen."

Isabelle smacked him. It hurt. Supernatural pop culture had not prepared him for Isabelle in the slightest. "Don't you dare laugh, vampire. This is serious."

He grabbed her offending hand and stroked her fingers gently, "Nah, no way. Those two? Back together by next week."

She smiled faintly, "I hope so. Alec hasn't smiled since he told us." She loved her brother so very much. He had used to wonder if her love for Alec had taken up her whole heart. He knew now that nobody had a bigger heart than Isabelle. She suddenly wrinkled her eyebrows, "Lederhosen? I will kill Magnus. Bad enough he can't remember your name, now he wants to make you look ridiculous?"

Simon laughed, "Better you than I."

"Us," Isabelle corrected gently, "I think 'us' sounds better."

A collection of sizzy drabbles. Please request a drabble at my tumblr, seveninchessimon. Comments are welcome!