Not mine, it belongs to Cassie, we know the drill. Enjoy the plot bunny, and Merry Christmas!

It was eleven o'clock in the morning on Christmas Eve, and Clarissa Fray was not amused.

"Jace, no."

Her boyfriend frowned for a moment, then smiled a huge grin, his golden eyes sparkling with suppressed humor.

"Why not?"

"Because that's... that's just cruel and unusual!" Clary shook her head. "How would you feel if he did that to you?"

Jace chuckled and raised an eyebrow. "Alec is somehow going to sneak up on me?"

Clary paused for a moment, biting her lip. "Fair point."

Jace smirked and continued throwing fake snow on the floor. Clary followed behind him, lugging the heavy sack of white fluff. She'd have never guessed that the Shadowhunter residents of this Institute would be so dedicated to celebrating the holidays, but celebrate they did, and in style.

The Institute was lovely, and considering how long they'd been decorating- since the first week of December- it should look nice.

Finally, Jace threw the last handful of white powder in a corner and grinned. "Done."

Clary rolled up the empty sack, walking over to Jace and tucking it into one of the many pockets of his gear pants. He looked down on her, his grin softening into a smile. He pointed up.

"Mistletoe," he murmured to her, the bright gold in his eyes darkening a couple of shades. Clary raised an eyebrow.

"Well, we'd best not break tradition."

He reached down to pick her up just as she jumped up to wrap her arms around his neck. They had this sort of thing down to a science by now, their height difference making such things necessary. He kissed her softly. Just as Clary felt she might go crazy with love for him, he pulled away, a little breathless.

"Please help me tonight?" Clary nodded mutely, more interested in the pressure of his mouth on hers than what she was agreeing to. Jace grinned and kissed her again.

It wasn't until ten o'clock that night that Clary realized what she promised him in that moment of desire.

"You're a cheater," she whispered to him, twirling the stele in her fingers anxiously as they made their way down the snow-covered hallway, aided and abetted by a Soundless rune. Clary had not quite been able to fight the laughter when she saw Jace come out in his pajamas- Jace didn't seem the type to go for cliché Christmas pajamas, but there he was in the red and white pajama pants and nothing else. Barefoot and bare-chested, he gave her a quick kiss and immediately pulled her back into his plain white room to explain the plan.

That was the last time she'd laughed.

"Jace! That's cruel!"

"No, it's a cool Christmas gift."

"For you, maybe! I doubt Alec would agree."

Jace shrugged. "I bet he would."

Clary just shook her head at him. "Don't fool yourself. There is no way on this world or any other that Alec Lightwood, your parabatai, would approve of this."

"Oh well, because it's happening." Jace bent over and scooped up a bag from the floor, making whatever was inside of it crinkle as it was jostled. "Now rune up and let's go."

So she had. And now here they were, skulking along the deserted Institute hallways. Clary had to fight the urge to start humming the Mission Impossible theme, a reference she was confident Jace would not get. Instead, she followed behind his silent form until they stopped in front of one of the many bedrooms, although this bedroom held their target.

"Have the Portal ready," he whispered as he took the bag and slipped inside.

"This is such a bad idea," Clary replied, but she still began drawing the runes on the wall.

Inside the room, Jace carefully set down the bag and drew his own stele. While his parabatai may be a heavier sleeper than he himself was, that didn't mean he would sleep through what Jace had planned. Carefully and silently, Jace drew a small rune on Alec's neck. Dormis.Sleep. Alec took a deep, shuddering breath, and he seemed to relax a bit. Behind his eyelids, his eyes flickered. He was fast asleep now. With a grin that would be described as psychotic by any person, demon or otherwise, unlucky enough to see it, Jace started to work.

Half an hour of waiting later, Clary stood up suddenly from her spot against the wall as Alec's door slowly opened.

"Cover your eyes," Jace advised as he dragged the still-unconscious form of his parabatai out into the hallway. Clary, as per usual, totally ignored his advice. The second she caught sight of Alec, she gasped and covered her mouth to hide her reluctant laughter.

"You're terrible!" She managed to get out between giggles. Jace crossed his arms and looked down at his parabatai, ridiculously proud of his plot.

Alec lay on the floor of the Institute hallway, fast asleep and with a little smile on his face. Clary hoped he was having good dreams, because he would find himself in a nightmare when he awoke. He crinkled a little with every deep breath as the rise and fall of his chest caused the ribbons wrapped around his bare chest to move. The only thing he was wearing, beside the ribbons, were a pair of Christmas-themed boxers decorated with little jingle bells and a Santa hat perched jauntily on top of his messy black hair. In the middle of his chest, there was a huge red bow. Attached to the bow was a small card dangling from some shiny thread. Curious now, Clary knelt down to read the card.

'Dear Warlock Bane,'' the card read in an unsurprisingly familiar cursive. 'Here's hoping you have a very Merry Christmas. Hope you enjoy your present.'

Clary looked up at his smug grin and shook her head. "Why do I feel like you'll be regretting this when everything is said and done?"

Jace looked totally unruffled. "Because you're suspicious?"

"Or smart." Clary countered before sighing and stepping aside, adding the last rune to the sequence for the Portal. "Send him through so I can go home. Mom's expecting me before midnight. We always spend Christmas morning together." Blushing under Jace's scrutinizing eyes, she brushed her hair behind her ear and replaced her stele. "Hurry up, the Portal won't last forever."

With a grin, Jace stepped through it with his unconscious burden. On the other side, he quickly laid his parabatai on the bed before jumping back through the closing Portal, smiling at Clary like he'd done nothing more interesting than take a walk down the dark hallway. Clary shook her head at him.

"I'm washing my hands of this," she told him, holding her hands up in surrender. "I'm not coming to bail you out of this tomorrow."

"You won't need to," Jace assured her, giving her one more goodnight kiss before she turned from him to draw another Portal on the wall. She looked back at him as she stepped through, getting one more glance at him, standing alone in the dark hallway in his Christmas pajamas, before the Portal closed. With a yawn, Clary walked out into the family room to check in with her mother and Luke, accepting the usual disapproving look about Jace with what she hoped was good grace, before returning to her room for bed.

Tomorrow, she'd check in at the Institute. Maybe she'd even apologize to Alec, explain that Jace's form of coercion was almost impossible to escape. With that thought in mind, she pulled on her own Christmas pajamas- her own dirty little secret, considering she had no right to make fun of Jace's Santa pajamas only to wear a matching nightdress at home- and slipped under her covers, closing her eyes and waiting for happy dreams to find her.

It was a loud thump that woke her the next morning.

Clary jerked awake in the pre-dawn light, too tired to register just how early it was. She grabbed the throwing knife from her bedside table, trying to blink the blurriness from her vision, and sat up, holding the knife defensively, ready to attack whatever dared intrude on her bedroom this early.

"You look really sexy with bedhead, you know."

Clary gave a little scream before the familiar timbre of the voice registered in her conscience. Her entire body sagged with relief until the fact that her boyfriend was in her room on Christmas morning registered in her exhausted brain. She peeked over the side of the bed, and had to stifle her laughter.

For some reason, on the floor of her room, there was a present she would have never expected outside of her wildest fantasies. Jace smiled up at her, seemingly unconcerned about his lack of clothing despite the cold of the morning. "Cute pajamas," he said with a self confident smirk. Clary pulled her covers up to her neck, but her green eyes sparkled in amusement.

"Yours aren't too bad yourself." Clary bit her lip, taking her time to look him up and down. Jace chuckled, somehow managing to roll up onto his knees despite the elaborate ribbon that was his only attire, obviously tied to keep him immobile. He seemed totally comfortable in his own skin.

This didn't change when Jocelyn walked in, either.

"Clary, sweetheart, it's time to wake up," Jocelyn said softly, not noticing Jace on the floor of the room at first. "It's Christmas mor-" Her comment suddenly cut off as she caught sight of her daughter's boyfriend, kneeling next to the bed, showing way too much skin to be appropriate. Clary's eyes went wide.

"Uh, mom, listen, this really isn't what it looks like..." she stuttered, trying to think of a safe way to explain things. Next to the bed, Jace grinned, obviously not self-conscious in the least.

"Merry Christmas, Ms. Fray."