This is my version of what I think happened when Jace entered Clary's bedroom the night before the big battle. Warning, this is a one shot lemon, if you don't like it then don't read it. And this story hasn't been edited by a beta.

I acknowledge that the Mortal Instruments world belongs wholeheartedly to Cassandra Clare. The Italics are from the book so I could set up the scene.

His hands lay flat on either side of him his arms at his sides, he seemed barely to be breathing; she wasn't sure she was breathing herself. She slid her own hand across the bed sheet, just far enough that their fingers touched-so lightly that she would probably hardly have been aware of it had she been touching anyone but Jace; as it was the nerve endings in her fingertips prickled softly, as if she were holding them over a low flame. She felt him tense beside her and then relax. He had shut his eyes, and his lashes cast fine shadows against the curve of his cheekbones. His mouth curled into a smile as if he sensed her watching him…

Clary felt herself smile in return as Jace's eyes fluttered open revealing the black pools under them. She could have spent the rest of her life just like this but shuddered at what reality pushed through her mind. Guilt threaded into her heart, piercing it with such ferocity that she had to break Jace's gaze and look away so he couldn't see herself being torn apart. Clary felt a hand cup her chin as it turned her so she was facing the owner. Jace looked at her with hurt written on his face. "If you want me to go I understand, all I ask is that you be honest with me, please tell me what you are thinking" he pleaded

"No, please don't go, I want you here I really do, but I just feel so guilty about what we're doing. I want you so much Jace that it is hurting me. Please don't think me selfish, but I couldn't let you go right now even if you wanted to."

Even if Clary wanted to say more, she wouldn't have been able to because it would have been muffled by Jace's lips as he leaned over to kiss her with such emotion that she did all she could not to cry.

"Tell me you don't want this Clary, please tell me that you want me to go, I can't keep myself away from you anymore. I need you to tell me Clary!" Jace all but screamed as he broke away from the kiss.

"I can't do it Jace, I would be lying if I did" Clary reached up and grabbed his face as she came closer and stopped anything he could say with another kiss. This time the kiss was more passionate and fierce, but she didn't care, she wanted him and that was all that mattered.

Jace rolled on top of her and moved his hands above her to support his weight. Soon enough they broke apart as oxygen became a must for the both of them. Clary was overwhelmed with her thoughts of how wrong this was, but how right it felt. What was she doing letting this happen? She felt so confused. Jace through half lidded eyes looked down at her with confusion etched into his eyes, was he thinking the same thing as she was? Was he thinking that all this was wrong and was about to leave? Clary didn't want him to leave and asked the only thing that could come to her mind.

"Jace, this could be the last night we spend here on earth, and if either of us doesn't make it I want to at least know that we loved one another and that we did what we felt right. Please Jace, I want you, I don't want anyone else in the world but you, can you please be with me tonight?" Her heart froze as she poured out her most wanted desire to the one person that she should never have wanted it with.

"Clary, Are you sure this is what you want? I don't want you to regret anything and this seems like a big risk to take. Don't think that you're pressured to do this, I need to know if you mean it." Jace looked like he was in hell at the moment as he was seemingly struggling with his conscious.

"Yes I mean it Jace, you're the only one I can think of to spend the last night of my life with, If we don't do it now then we will never have the chance again, and I couldn't live with that. I mean it Jace, I love you, I always will"

Without another word Jace leaned down and tenderly caressed her lips with his. Clary reached her hands down and slowly started lifting his shirt off. Jace reacted by breaking the kiss so he could pull it over his head and fling it on the floor.

There was little light as the curtains didn't allow much to come through, but she could still see the silvery remains of the marks that Jace had etched into him from years of being a shadowhunter. To a mundane they would have been strange, but to Clary they made him even more beautiful to her as they showed much more then just scaring. Her mind came back to reality as she felt Jace slip a hand under her camisole and started rolling it up her body. She all of a sudden felt very nervous and went to stop him but then stopped herself as she stared up at him and felt all her thought wash away in one wave. This was Jace, the man she loved with all her heart, she shouldn't be worried about what he would this once she was exposed. If he really did love her then she would be fine. With that thought she put her hand on top of his and helped him undress her.

Soon enough they were both undressed and both flushed beyond belief. Each other thought the other was the most beautiful thing they'd ever seen. Not only had they lay bare to each other, but they had also exposed every emotion, every thought and fear ever held to each other with just the simple expressions they wore. There was no shame for what they were doing, Clary believed whole heartedly that they were doing the right thing no matter what anyone else thought because it was between them.

Clary made the first move after that moment by putting her hand on his chest. This brought Jace out of his trance and he moved to put the covers over them both so as to have some modesty. He then reached for Clary's hands and clasped them in his own. They stared into each other's faces as Jace spoke.

"Are you sure?"

"Yes, I love you"

"I love you too"

And they were the last words that were to be spoken that night.

Jace let go of one of Clary's hands and slipped his own down under the covers. Clary held her breath as she knew what was coming, and felt him and he placed himself at her entrance. While they watched each other, Jace slowly but surely slid into her and she gasped. Clary had known about what would happen, but she had never experienced it before, it was like nothing she had ever felt before. She felt the pain as Jace pushed through her barrier, the one sign showing her innocence was now gone, but she was glad of who it was that took it. The pain shot through her spine, as he moved in and out of her but she didn't show it because she didn't want Jace to feel bad, Clary knew that soon enough it would feel better and she was right.

Within moments pleasure started creeping up as Jace started to move faster in and out of her. Clary started moaning in satisfaction and was about to suppress it only to realise they were the only two people in the house. Jace looked up at her and smiled in response to her noise and quickened his pace again to get another moan out of her. All they could do was stare at each other as they made love. To them it felt like they were the only two people in the world and all their worries had vanished. Clary felt Jace harden even more and he grabbed her free hand and placed them both up above her head. Clary started to meet his rhythm by rocking back and forth in time with his strokes. It seemed to have the desired affect as Jace went harder and deeper into her all the wile groaning in pleasure himself.

In all it took only a short amount time for them to reach their climaxes as Clary came screaming with Jace following suit, emptying himself in her. To them it felt as if time had stopped and granted them this moment for the rest of their lives. But a moment later Jace had withdrew himself and rolled off Clary and lay panting on the bed beside her, a layer of sweat coating his body. With a last look Jace smiled at her as she moved to lay her head on his chest and he moved his arm to wrap in around her. The covers lay just below their waists and neither had the energy to move it to put over them.

Soon Clary could feel the rhythmic rise and fall of Jace's chest, a sign of slumber to any human. And with that Clary felt the onslaught of tears that had threatened to spill from the moment he had entered her bedroom.

What had she done?