So this takes place after CoHF. In CoG Isabelle wrote a note with lots of x's and o's apparently, and then I started wondering if that was just a mundane thing, etc, and it spiraled into this. Sorry.

She clutched the scrap of paper in her hands, crinkling the sides. She read it over for what had to be the millionth time. Thanks to the memory rune on her neck, she had memorized the words after reading it once, but she still frantically searched the paper. She had to have missed something, some sort of clue or hidden message.

Hey Izzy,
Sorry I couldn't be there this morning, but Rebecca called and wanted to see me. Shes only in town for a couple day, so I hope you'll understand. I'll come by the Institute later.
XOXO,
Simon

XOXO. What did it mean? She had already rummaged through her mental library and all she had recalled was a small Mexcian city called Santa Cruz Xoxocotlán, sometimes nicknamed Xoxo. Somehow she doubted Simon had been referring to that. It didn't mean anything to her in any of of the languages she knew, although to be fair she only knew English, Latin, Ancient Greek, and Purgatic.

Her next obvious choices were to go to her brothers and see if they knew what it meant. Isabelle was worried. What if Simon had been taken against his will and the letters were a secretive signal for help? What if it was an acronym and stood for the place he was being taken? Or the person/thing that had taken him?

Seeing as she had stayed the night at Simon's, she would have to catch the subway or a taxi to the Institute. He had recently turned eighteen and moved out of his mother's house, and he had been continuing his training for Ascension. Because of that, she worried more. A Daylighter vampire turned Nephilim had the potential to make a lot of enemies, and seeing as Simon hadn't yet completed his training he might not be able to fight off everyone who chose to come after him.

After arriving at the Institute, she eventually found Alec and Jace in the kitchen, and once she realized how early it was it made sense. If she had been thinking straight she would have checked there before the training area, weapon's room, and library.

"You guys have to help me!" She exclaimed as she burst into the room, heels clicking against the tile.

She wasn't halfway finished with her sentence before Jace started pulling out weapons from various caches in the room. He plucked a few bottles of holy water from the fridge and with a nod of his head gestured for Alec to grab the silver knives from underneath the sink.

"So what are we talking here? Weres, vamps? Rogue warlock? Alec, where did we put the electrum chains for prisoners?"

"In the empty Raisin Bran box."

"Ah right," Jace said, snapping his fingers and reaching over to open the cupboard. Isabelle took a moment to appreciate the genius of that particular hiding place. Honestly, who would open a box of Raisin Bran?

Isabelle shook her head. "Not that kind of help," she said, waving off the seraph blade Alec tried to hand her.

The two parabatai froze mid-motion, Jace halfway through removing a wicked guisarme from under the sink and Alec taking out a quiver of arrows from a secret compartment in the microwave.

"Oh," Jace said calmly. "Well, that's disappointing."

Alec looked sadly at the floor. "I thought we were finally going to get to test the new explosives we made."

"Shut up, this is serious!" She snapped. She held up the crumpled note for them to see. "Simon's missing."

"Isn't that a pity?" Jace murmured to himself.

Alec aimed a sharp kick at his shins before turning back to her. "What makes you say that?" He asked, ever the careful one.

"He left a note." Isabelle handed it over to them, and the two boys moved closer together so they could both read it. "XOXO. It has to be some sort of message."

Jace frowned. "I don't know what it could mean." Isabelle slumped in disappointment; Jace knew the most languages out of the three of them, being able to speak and read Romanian, Italian, Latin, French, and probably a few others.

Alec bit in his lip, eyes focused like he was deep in thought. He knew more demon languages than she did, and Magnus had also been teaching him Indonesian. Finally, he shrugged. "Sorry, Izzy. Could it be a place?"

She shook her head, her dark hair swishing about her shoulders. "I already thought about that. All I can think of is a town in Mexico."

Jace nodded, immediately assuming the position of leadership, as was his nature. "Right. Alec, call Magnus. Get him over here and see if he can track Simon or help decipher the note. Isabelle, call Clary and make sure he's not just over at her house. If he's not, tell her to get over here. We might need her if we have to fight. I'll run down to the library and get some reference books. Maybe we missed something."

They all flew into action. This was what they trained for. They knew how to react quickly and formulate battle plans. And even if Jace personally didn't like Simon that much, he would still treat him as a fellow warrior. No man was left behind, and they had a duty to protect one another as long as they were capable of doing so.

Isabelle's worry began to grow into full blown panic when Clary told her she hadn't seen Simon, and the redhead sounded concerned when Isabelle informed her she was missing.

Clary and Magnus arrived around the same time, and at that point the three Shadowhunters were flipping quickly through large tomes and studying the note closely. Maybe he underlined specific letters to form a sentence, or misspelled words. They discovered that he left out an apostrophe in she's and forgot an s in days. That was all they had to go on.

Clary hung back slightly, peeking over Jace's shoulder to look at the text he was reading.

Meanwhile, Magnus sighed wearily and rubbed at his makeup-less eyes. "Alec, darling, I love you but this better be important. It's far too early to be awake."

"We think Simon's in trouble," Alec said, not glancing up from his book until Magnus forced his chin up in a brief kiss.

Magnus groaned. "Don't tell me. He's gotten himself bitten by a werewolf, is that it? You know, he almost has me feeling jealous at the number of species he's gotten to be. A mundane, a rat, a vampire, a Shadowhunter. It really wouldn't be all that surprising."

Clary piped up, ignoring Magnus's prediction. "Over the phone you said he was missing."

Isabelle nodded, pushing a lock of hair behind her ear. "We think he might've hidden a message in this note, but none of us know what it means. Magnus, do you think you can track him?"

The warlock rolled his eyes. "Biscuit, I'm a High Warlock. Of course I can track him. And what's this hidden message you're trying to decode?"

Isabelle motioned over Clary and Magnus and jabbed a finger at the cursed letters. "There. Xoxo. And before you say anything, we've already looked into the Mexican city thing and-"

She was cut off by Magnus lurching sideways and falling against Alec, successfully hiding his face from view. His body wracked with shaking motions and loud, indiscernible noises were rising in his throat.

"Magnus? Magnus, are you okay? Are you crying?" Alec looked positively alarmed at his boyfriend's state.

"I'm-oh, dear Lilith...I'm laughing!" He finally choked out, pulling away long enough to display a beaming smile.

Isabelle glared as she shoved her chair backwards and stood up. "Look, if you aren't going to take this seriously you can take your entitled, High Warlock ass and-"

"Isabelle," Clary interrupted, surprising her by giggling. Giggling. She was standing there giggling while her so called best friend was missing. "Simon's not missing. Look, have you tried calling him?"

"Of course I have," she shot back, annoyed that the other girl thought her stupid enough to not try his phone before jumping to conclusions. "It went to voicemail. It must be dead, he could have been taken hours ago."

Magnus eventually stopped laughing long enough to say, "Obviously you Nephilim need to get out more. Maybe it would help avoid these kind of situations." He moved so he could could put his arms around Alec's chest from behind, nuzzling the other's boys neck affectionately. Alec tried to scowl but ended up smiling instead.

"What do you mean?" Jace pressed, ignoring the fact that his parabatai was practically being molested by a warlock.

Clary rolled her eyes. "XOXO means-"

"Hey guys." Without warning, Simon walked into the kitchen, dressed in a Nirvana t-shirt and jeans and clutching a paper coffee cup in his hand. He glanced at the books scattered around the kitchen. "What's all this?"

"Simon!" Isabelle cried, launching herself at him without hesitation. It was only because of his partial training that he was able to catch her instead of falling on his butt. She littered kisses all over his face. "I can't believe you're okay." She blinked back tears that were threatening to fall, cursing herself for being so emotional.

"Um, not that I'm protesting this kind of greeting, but what's going on?"

"We thought you were missing, you ass!" She pulled back just enough so she could shove him away, crossing her arms and moving to sit back in her chair.

Alec spared her a brotherly glance before turning to Simon. "Where were you?"

"At breakfast with my sister," he replied slowly, still looking around the room in confusion. "Was there training scheduled or something?"

Jace raised a single golden brow, holding the note between two fingers. "You left this for Isabelle."

Simon nodded, a faint blush coloring his cheeks. He rubbed the back of his neck awkwardly. "Yeah."

"You left out an apostrophe and an s, along with writing xoxo. "

"Sorry?" It was clear that Simon was still massively confused. "I didn't know you guys moonlighted as the Grammar Police."

Clary laughed and Magnus smirked.

"So what was it you were trying to tell us?" Jace inquired.

"I wasn't trying to tell you anything. I was just letting Izzy know that I was with Rebecca."

"But you-"

Clary sighed heavily. "Jace, let it go. I'll tell you what it means."

"If you knew what it meant then why didn't you-"

"By the Angel, would you just shut up?" Clary managed to drag Jace away, even if he was still going on about the duties of the Nephilim and how if she had inside knowledge she should have spoken up, blah blah blah.

Magnus cleared his throat and straightened up. "Well, this has been fun, but we should probably go too."

Alec protested, "But I want to find out what xoxo means."

"Well first of all, darling, you're pronouncing it wrong. You say each letter individually. Secondly," Magnus leaned in and whispered something in Alec's ear.

Alec pulled away with an expression of disbelief. "You're kidding, right?"

"Nope," Magnus replied cheerfully, making a popping sound on the 'p'. "Now come on, I'll buy you breakfast."

Alec stood up and followed him out the door. "But why does it stand for that? An x doesn't look anything like-"

"We'll go back to my place and you can Google it," Magnus said, winking playfully at Isabelle before they left.

Then it was just the two of them. Simon took a seat next to her and set down his coffee - which had surprisingly survived Isabelle's attack. He coughed uncomfortably and started, "So...You mind explaining what all that was about?"

She frowned. "You left a note. I thought you'd been kidnapped while I was sleeping or something and were trying to tell me where you went or who took you."

To his credit, Simon didn't burst out in laughter like Magnus had done. However, he did snicker. "Sorry to disappoint, but I wasn't kidnapped."

She rolled her eyes. "Obviously." After several moments of a silence, she caved. "So what did it mean?"

"What did what mean?" He looked at her with genuine puzzlement.

Isabelle said, "XOXO. What does it mean? Was it some kind of code?"

Simon's jaw dropped open, and for a few seconds Isabelle thought he had gone into shock. Then he threw his head back and laughed. "Sometimes I forget that you didn't grow up in the same world I did."

Frankly, she was getting more than a little irritated that no one was telling her anything. Jace had probably found out from Clary by now, and Alec definitely knew. She hated being out of the loop.

"Just tell me what it means."

She wasn't prepared for Simon to suddenly pull her to her feet. Before she could react, he tugged her in for a tight embrace, only lessening his grip in order to kiss her lightly on the lips.

"It means hugs and kisses."

So I've been having a bout of writer's block. Hence: this. It's been in my drafts for a while now, half finished, so I decided to wrap it up. Leave me a comment telling me what you liked/didn't like.