For my wonderful reading buddy, who always encourages and supports me, despite the fact that I'm a little crazy, and that I think Jace is a real person, no matter how she tries to convince me otherwise.

An MI/HP crossover. There are NO CHARACTERS FROM HARRY POTTER IN THIS STORY. Just the Mirror of Erised. Clary/Jace.

Clary couldn't sleep. The Institute at night was utterly silent. In light of recent events, Clary's mind was already spinning, and the eerie soundlessness of the atmosphere pressed on her ears in a manner that banished any thought of sleep. The scene with Jace in the seelie court kept flashing across her eyes every time she closed them. The vivid memory of Jace's lips against hers was so real she could almost taste him. She rolled over restlessly, getting tangled in her bedcovers. She shouldn't think about Jace that way. She couldn't. He was her brother, her blood kin. She was fairly sure that, centuries ago, people had been executed for doing less than what they had. It was incest, it was unnatural. And yet, infuriatingly, she couldn't bring herself to be disgusted by it, as anyone else surely would be.

Clary tossed again. She was too awake, too hyper. Just the thought of Jace made her feel hot and uncomfortable. With a sigh, she sat up, and thrust the bedcovers away. Shaking curls out of her face, she swung her feet over the side of the bed and stood up. Her soft breathing was the only sound. She crossed the small guest room and stepped out into the hallway, closing the door quietly behind her.

Burning torches in brackets were spaced along the walls, illuminating the narrow corridor. Clary was slightly surprised; she had expected it to be pitched black. The flames flickered across the polished wooden doors of the other guest rooms.

Her feet seemed to move of their own accord, taking her past the closed doors. She wandered the identical corridors aimlessly, letting her feet take her where they would. She was almost in a trance, not exactly aware of what she was doing. She thought she had been walking for about fifteen minutes when she noticed that the part of the Institute she was in had not been occupied for what seemed like a long time. The walls were blank and dirty, with no doors, windows or even the carvings that seemed to be everywhere. The cold stone floor was thick with dust, Clary's footprints clear against the filth. Clary kept walking until finally the passage ended. She was facing a dead end.

Nice, Clary, she thought to herself, way to get lost. She wasn't lost of course; she could easily follow her footprints back to a corridor she recognized. Cursing her pointless actions, she turned to do just that, when she noticed something from the corner of her eye. She turned back again.

The door on her right was exactly the same dusty colour that she hadn't noticed it before. It was made of very weathered, pale wood. At first, Clary was reluctant to tough it. It already looked as if any moment it would fall off its hinges. But she figured that if she had come this far already, she may as well see what was in this room that everyone so clearly avoided. Stepping forward, she pushed the door open and went inside.

The room looked just as abandoned as the corridor outside it. Cobwebs hung thickly from the ceiling, covering the rafters in a grey sheet. It was completely empty, except for a magnificent mirror, as high as the ceiling, with an ornate gold frame, standing on two clawed feet in the corner. It was as dirty as the rest of the room; there was a barely legible inscription carved around the top: Erised stra ehru oyt ube cafru oyt on wohsi.

Clary frowned, staring at the strange words. It didn't look like Latin or Greek, or any language she'd ever seen. She looked harder. Erised. The word looked familiar, but she wasn't sure how. It was something to do with the letters.

Desire. Erised was desire spelt backwards. Fascinated, Clary stepped closer, examining the end of the inscription. But this time, she read it backwards.

I show not your face but your hearts desire.

Clary smiled bitterly at the irony. Desire would be familiar to her, for sure. She was sick of it. If she doesn't desire his kiss, she won't be free, the queen had said. And she had desired it. More than anything she had ever desired before.

But then there was the question of why the mirror was down here. Was it broken? Pushing her pain away, Clary stepped in front of the mirror.

Her scream was not heard or answered. She whirled around to look behind her. She was alone, faced with nothing but blank stone wall. Slowly, she turned to face the mirror again. In light of the inscription, what she saw was painful, but entirely expected.

There she was, pale and dishevelled-looking. Standing next to her, with his arm around her shoulders, was Jace. He was smiling at her. The mask of arrogant sarcasm and sardonic humour he usually wore was gone, replaced by an expression of true happiness. She had never seen him so utterly defenceless, the walls between them gone. Tears welled in her eyes, spilling rapidly over her cheeks and falling softly to the floor. It's not real, she told herself, trying to push back the mixture of joy and agony that she felt. The Jace in the mirror reached across and brushed away her tears, tightening his arm around her shoulders. He lovingly kissed the top of her head. She glanced sideways, to the place where he should have been standing. The moment she looked away, the phantom arm she could feel around her was gone. A sob wrenched its way from her throat as she turned back to the mirror. She could feel him again, feel his non-existent body heat, his loving touch. She wrapped her arm around his waist and leaned her head against his shoulder, meeting his eyes in the mirror. Tears were dripping from the end of her nose. Her tiny frame was shaking with sobs. Jace pressed his cheek to her hair, brushing away her tears with his free hand.

If the institute had not been so deathly silent, aside form her own crying, Clary would never have heard the soft brushing noise coming from the doorway. Her head whipped around, only to see the room exactly as it had been before. Church.

Clary turned back to the Jace in the mirror. Her sadness intensified at the thought of leaving him. "I'll be back," she whispered, "I promise." Jace smiled at her again, bending and kissing her cheek. Ducking out from under his arm, Clary crossed the room, heading for the door. She could have sworn she could feel the tearing separation as she left a part of herself in the room, with the mirror, with Jace. That piece of her that would always belong to him.

Following her own dusty footprints, she made her way back to her room, stifling her sobs as she went.

Now, people, you have to review and tell me what you want here. In the next chapter, should Clary and Jace act like Clary and Jace, or should I just throw reality to the winds and make them 'hook up,' so to speak? This story is about giving the masses what they want. The majority vote wins.

Oh and by the way, the next chapter probably won't come out for a while, what with So You Think You Can Dance Australia and House coming back on, as well as the whole 'Back to school' thing. But if I get enough reviews I might hurry up a bit. ;) Please review!