Summary: What if Clary knew Jace, her Jace, was gone forever, and all of the sudden, she realized that Sebastian was who she belonged to now? It starts right when Sebastian kisses Clary after he repairs Lilith's rune on Jace's chest. Rated M because it is super citric concentrated lemonade!

Disclaimer: I owe none of the characters on this fanfic or the quote from which this story departs from which is originally written by our lady, Mrs. Clare on City of Lost Souls.

"Belonging"

"She raised her hands meaning to shove him away. "I don't belong to you. I belong to me."

The look in his eyes froze her in place. "I think you know better than that," he said, and brought his mouth down on her, hard." (Quote from City of Lost Souls, Chapter 19th)

For a moment, Clary felt disgust. She tried to push him away, but the more she tried to fight him, the more Sebastian seemed to get turned on. She managed to get her right hand free, lifted it and grabbed onto his silvery blonde hair, she pulled hard trying to get his mouth to release hers. Yet, in the process of pulling his hair, without consciously realizing how it happened, she found herself kissing him back.

And all of the sudden, it didn't feel wrong anymore. He had been right, mundane's laws didn't apply to them. How could this be wrong when it felt so right?

Clary couldn't get enough of the way his lips felt on her, how his body was so closed to hers that she could feel his heart beating faster and faster, and the way his touch was leaving a burning trail everywhere he touched. She was able to tell the minute he truly noticed she was not fighting him anymore or resisting because she felt him immediately replaced all of his anger for joy. At first he had hesitated when she had started kissing him back, probably distrusting her, but then she could feel the smile on his lips and then the only feelings she could sense coming from him were joy, lust and… love?

She couldn't tell.

She was not thinking, she did not want to think, all she knew was that she did not want him to stop kissing her, touching her, pressing her against that wall. When he let go of her mouth to ask her "Do you still believe you belong to yourself?" a small whimper escaped her lips. When she finally found her voice, her answer surprised her; "No". That was all she said, so he asked "Do you belong with Jace?"

Even though she could feel the guilt inside her somewhere, she said "No". She knew she was not lying because she felt in her heart that she was being truthful. She knew she could never belong to the Jace who-is-not-her-Jace. Still, a small part of her soul was shattering for her Angel boy… that part of her still loved him, but the rest of her being knew now that he would never return to her. Even if he did, how could he possibly forgive her after this?

She shut her eyes tighter, a small tear running down her right cheek.

Sebastian licked her tear away and kept on trailing kisses down her neck to the top of her breasts, kissing, licking, teasing, biting, and sending waves of pleasure throughout her body.

Finally, he asked her with a husky, sensual, and yet hesitant voice, "Who do you belong to, Clarissa?" Before she could even begin to answer, Sebastian's right hand started making its way up her thigh, his fingers barely touching her skin. All the roughness from his first touches had been replaced by feather like caresses. It was like he was trying to lure her with his electric touch. Clary tried to clear her head, but Sebastian kept on drawing circles that kept on trailing upwards towards her center. She was burning with desire; she could not understand what was happening to her. Jace's touch had never made her feel physically in pain from desire like Sebastian was, she felt like she was on the ledge of a building, ready to jump, but being held back by a power field. All the while Sebastian kept on teasing her not reaching her core, not giving her the friction she felt she desperately needed.

He asked once more, "Who do you belong to?" trailing her slit with one of his fingers just once through her panties. She bucked her hips forward but he used his own hips to keep her still, not allowing her to get any relief from the touch.

Licking her ear lobe, he whispered in her ear, "My love, you have to tell me if you want me to continue… who you belong to?" She knew that the minute she said the words, they would become her truth, she didn't want to say them even though she believed them now, especially after hearing him calling her "My love".

Her brain could not make sense of anything, there was an overload of emotions, sensations, of everything… she started crying instead of answering, but Sebastian only said "We can make the angels be jealous if you just let go and tell me, who do you belong to?". He bit down on her shoulder and kiss her, all at the same time as pressing his want harder into the space in between her hips. She moaned loudly and felt him smile on her neck.

Finally, she closed her eyes and said "I belong to you now" as soon as she admitted it, Sebastian grabbed her from her rear and lifted her up to his hips, he carried her to the master bedroom in which their father had once slept and said "And I belong to you, now and forever"

He set her down on the bed and stepped back. He turned the lights on and started unbuttoning his shirt. Clary could only stare in awe at the beauty of her brother. His eyes always dark seem to be shiny and as full of life as she had ever seen them. He smiled and walked towards her. He bent down and kissed her, this time softly but passionately. His warmth made her arms shoot up and wrapped around his neck to keep him close to her, and to help her deepen the kiss even further. He complied and while kissing her he lifted her up towards the center of the bed. He hovered on top of her, kissing her, touching her face. He let his touch drag down her collar, and in a quick jab, he ripped the fabric of her top in two. Then, he looked down at her and candidly said "You are so beautiful… and all mine". Clary felt like she was in a dream, she could not believe she could possibly want him. She knew she should be resisting, she should be fighting, she should hate him, but a part of her kept asking the same simple question; why? If she felt this good, this right, this overjoyed with him, why was she supposed to hate him? Only one possible answer came to her mind; Jace.

Suddenly, she remembered Jace. His golden eyes, his bronze skin, his crooked smile, the ways his arms felt, his smell, his voice… his kisses. She longed for Jace. A part of her will always belong with him, but if he was gone forever, why keep on trying to deny what was happening to her right this second?

Sebastian's hands on the clasp of her bra brought her out of her mind, his knowing hands opened the front clasp quickly, releasing Clary's creamy breasts and rose colored nipples. As soon as they were free, his tongue teased the tip of her nipple and she felt and electric shock down her spine all the way to her center. No one had ever touched or seen her naked, and somehow, she felt no shame. It felt completely normal, as normal as a couple kissing on their wedding day.

The initial shock of having Sebastian's burning hot tongue teasing her nipples and her hands over her breast gave pass to a boost in her desire. She could feel her panties getting wetter, and the pain right in the center of her core starting to come back. It came back pulsing like a heartbeat, making her want to trail her own hand down there to calm the pain. Instead, she wrapped her legs around Sebastian waist and pushed his hips down on her while lifting her center to meet him. She could feel him hard under his pants, she was getting impatient and Sebastian could tell. He said "I want to take my time tasting all of you" the promise in his words got Clary even more impatient, all she said was "Please" He chuckled and said "No need to beg my beautiful one, just relaxed and let me show you I can give you a better time than Jace"

At the mention of Jace she felt again the same guilt for what they could have had, together with a new guilt, that of letting Sebastian believe that she had slept with Jace. She couldn't stop herself from telling him the truth right that second. "I never slept with him" she said hesitantly. For once, Sebastian seemed clearly surprised. He stopped all of his actions completely, getting him a little gasp from Clary. He moved back and looked into her eyes and said "Tell me the truth… please" She lowered her eyes, feeling embarrassed for the first time and said "I did not sleep with Jace… or anyone for that matter… I just let you believe it because I was angry, but it was not true"

She looked up at his shiny eyes again and all of the sudden his mouth was on hers again, his hips grinding into hers, his hands touching her harder, more desperately. Once he moved from her mouth he said "You are my angel… maybe that's why Lilith brought me back" She wondered what he meant by that but all of the sudden his lips were trailing kisses down her body again and she forgot that she wanted to ask anything. He started unbuttoning her jeans and quickly had her out of them. Then, he started making his way up the inner side of her legs, trailing wet paths with his tongue and spreading her legs while doing it. Finally he got to her center. She still had her panties. He breathed deeply and moaned. Then he started passing his tongue through her panties. Just the contact of his tongue to her core, even through the panties made Clary say his name with a pleading tone. He put his fingers through the bottom of the fabric and ripped it quickly. Immediately after, he moved his tongue through her slit licking all of her wetness. The pain at the core of her intensified and again she said "Sebastian, please". His reply to this was to push his tongue hard right to the spot where she felt she needed it the most. His tongue was twirling and licking and pushing and it didn't matter what it was doing, it was working.

Clary felt the tension on her lower stomach intensify and build more and more. Sebastian was completely lost on his need to taste, kiss and consume all of her. Clary told him then, "Sebastian, I need you… now, please". He looked up at her and she saw his eyes darken even more for just a second, but then, they softened and he said "You are not ready for me my love, I don't want to hurt you… I can't hurt you". Clary pushed her hips forward trying to show him that she was more than ready for him, that her body needed him, but he caressed her face and said "Do you trust me, my angel?" The answer to that question only an hour before would have been "hell no!" But now, it seemed like everything had changed. She had changed. "Yes" she barely whispered and once again pushed her center towards him, this time rubbing herself against his hard on. He closed his eyes for a second lost in the sensation. He knew the demon inside him wanted nothing more than ravishing Clarissa with no trepidations. He almost wanted to let him take charge and do to her all of the things he had been dreaming of for months now. He couldn't. He knew that if he did, than she would be hurt. His angel would be hurt and damaged. The demon part in him would want to hurt her. He could not let himself allow that, not now, not when she had finally understood what he had always known… They belonged to each other. So instead of letting the demon out, he pushed out the part of him that was Jace's.

When he had drank of him something had clicked deep within him and changed him. It was like Jace's blood, Ithuriel's blood, had awoken in Sebastian the side in him that was good, the side of him that was Jocelyn's and Valentine's, the side of him that was not infected by Lilith's evilness.

He now pushed that side of him forward. He told Clary, who was still rubbing herself against him trying to get her release, "Love, I'm going to touch you now, you need to promise that you'll let me know if I'm hurting you" She just nodded quickly. Sebastian brought his lips back to her mouth, kissing her deeply, gently. Her hands pulled on his unbuttoned shirt and she let it fall to the side the bed. She touched his strong, muscular arms and then brought her hands to his chest. When her fingers unintentionally caressed his nipples he pushed his hips harder into her center and she moaned in his mouth at the feeling of him. He stilled but then quickly relaxed. She kept on rubbing his nipples sending waves of pleasure all through his body. All of the sudden, she realized that while she was naked and his hands were directly on her arms, on her belly, moving slowly down, he was still wearing his pants and boots. She lowered her hands on his stomach, following the line of his abs down onto his hips and then inwards following the lines of his V-shaped muscles. Right in the middle, she started opening his buckled and then his button. His hand moved quickly to her right thigh where he let it rest. When she lowered his zipper and reached into his black silk boxers for his member, his hand squeezed her thigh sending her into an accumulation of energy. She was barely able to wrap her hand around him and her eyes widened at the prospect. Sebastian noticing the worry in her eyes said "Relax my love; I'll make you ready for me… I swear I will not hurt you". Clary just nodded and started stroking him hesitantly. She felt then Sebastian finger move along her and finding her little nub. He started drawing circles there, softly but applying the right amount of pressure. Then, he moved one of his fingers to her entrance and draw circles there. At this Clary lost control and pushed her hips forward. At the same time, Sebastian pushed his finger inside her carefully. She felt a bit of discomfort for just a second and then her want for him seemed to grow even more. He started moving his finger in and out, giving Clary exactly what she needed. Then, he put another finger in. A soft stab of pain shot through her, she opened her eyes to see him watching her while sucking on her breast. The sensations were too much. She started pushing her hips forward to meet his fingers. She barely registered him inserting another finger and moving them in and out of her as well as around. He was stretching her, readying her for him. All of the sudden, Clary could not think, see or even breathe anymore. She heard Sebastian whispered in her ear "Come for me my beautiful" She felt herself tightening around his fingers, her nipples hardening even more in his mouth and then, everything was gone. It was like she had been cut from gravity and was floating lose. She felt her body melt and all she wanted was to never be put together again. All too soon though, she fell back and opened her eyes to see Sebastian smiling at her, his hand still touching her core reverently. He kissed her lips once more, and started moving down her body. He reached her core quickly and started licking all of her cum. She thought she was going to die. She felt her body was throwing glowing sparks and it was even more sensitive than the first time he had done this. She felt the tension that had been released from her belly just a minute ago start building up again with even more intensity. This time, she knew she was ready and she let him know. She said "I want you to make love to me now; I need you to be part of me" He stood up quickly for just a second to remove his pants and his boxers completely. Clary looked at him naked for the first time. She had never seen a man completely naked in her life, but the sight of Sebastian made Michelangelo's David a horrible spectacle. He was moving swiftly to get back to bed and into her but she blurted out "Wait!" He stopped immediately, thinking that she was going to reject him, that she had decided that she didn't want him, that she had been lying when she had acknowledged she belong to him. And even though he felt rage for a split second, he stayed still. She stared at him and said "You are an angel too". He looked in her eyes and saw love and admiration. He had never been loved before and the feeling overwhelmed him. He got back into the bed and kissed her while positioning himself at her entrance. He looked into her eyes for reassurance and she nodded slightly. He pushed in just the head and saw Clary close her eyes. He stopped but she opened her eyes immediately and with a look encouraged him to continue. He kept on pushing in until he met her barrier. He brought his lips to her mouth, his hands held her hips and then he pushed all the way through. She cringed for a second and then relaxed into him. She kissed him harder, hugged him harder. Then, he started moving in and out, slowly, carefully, deeply. She opened her legs even more to allow him to penetrate her deeper. He felt himself touch glory. She was so tight. He had never felt anything like what he was feeling right this minute, being inside his sister. She started to pick up the pace and now she was moving with him. Her hands were no longer hugging but pushing. It was like she was trying to melt him into her. He was pumping into her in a steady pace. He wanted to let go so bad, just go full on until she could not breathe, but he held back, he knew that later on there would be time for rawness. Now, she needed him to be gentile, however that did not mean he couldn't go deeper and faster. With him being on top, he had full control, he liked that, but all of the sudden, Clary shifted her legs and for a second he thought he had died. The sensation of being that far into her overwhelmed him and he felt that his build up was starting to drag him to the edge. He could not allow himself to let go without Clary, but they were so connected that as soon as he started to get there, she was just one step ahead. She begged him "Harder, harder pleeeeeease" And he complied with a smile. He pounded into her depths harder and felt himself start twitching inside her while her walls strangled his member with her coming hard. She moaned loudly his name in a high pitch "Sebaaaastiaaan" and that was what brought him over the edge. He spilled his seed inside her like a bomb and it was so hot that she felt burning inside her loins and came again a second and third time. He kept on thrusting into her for the next whole minute sending her into multiple orgasms while riding out his. Then, he collapsed into her, kissed her and whispered "You are mine… forever" to what Clary just replied "Yours"

A minute passed and she heard the front door. She felt Sebastian tense for a second and then relax. She looked up only to see Jace staring back at her with an expression of confusion at first and then… acceptance.

That's when it all came back to her… this Jace was not her Jace anymore because Sebastian was controlling him, and now, he was controlling her as well.

Sebastian just hugged Clary tighter, a smile spreading across his face while staring at Jace.