I know some other people have written about this but I really wanted to do one myself.
Disclaimer: I don't own and characters of the Mortal Instruments
Jocelyn ran down the steps of Amatis' house. She almost fell on the stairs, and looked back to see Clary giving her a reassuring look. She charged on, and as she turned the corner she saw Luke halfway down the block. He stopped and turned to look at her. He looked tired and very sad. She dashed up to him and started to speak,
"Luke" Jocelyn said sadly, "I'm so so-" Luke cut her off
"Jocelyn, you don't need to apologize." he told her wearily, "There is nothing more to be said, I know that you could never return what I fe-"
"No Luke, you don't understand" she took a deep breath, "I do love you, I always have." He raised his eyebrows in response
"Jocelyn, you don't have to say that just to make me feel better." His surprise had vanished replaced by realization, "I know that you consider me a friend, I just needed to tell you the way I felt, I didn't expect you to return my feelings. Faking your feelings won't make it any better, because I'll always know that you could never really-" He choked back tears, unable to finish his sentence. He turned to go, his eyes shining. he didn't want her to see him cry. She grabbed his hand, and he turned back around, reluctantly.
"I know you're trying to help Jocelyn, but when I looked at you it's like needles stabbing into me. I know we can never be together if you don't truly love me."
"Luke, I'm not lying to make you feel better, I'm telling you the truth to make you happy" she said exasperated, "I love you" she breathed the last words in one breath, "Please tell me you believe me" A single tear slid down her cheek. She lifted her arm up to wipe it off, and when she looked up Luke was closer to her, she held back a gasp of surprise. He put a hand up to touch he cheek, still unsure, he paused.
"How long have you felt this way?" he asked amazed
"When I found out Valentine was evil, I hated him and you were there for me to help me through it. You even left you pack and came to New York. How could I not love you, so kind, and soft..." She trailed off, because Luke was smiling,
"I've waited so long for you, Jocelyn, and now I can finally be around you knowing you want me too. I love you with all my heart, and I will always be there for you, forever." She was still holding his wrist, he took her hand instead and wrapped it in his. When he looked up she was crying tears of Joy. He gently touched her cheek with is other hand and cupped he face in his hand. He kissed her then, slowly at first, making sure he wasn't dreaming, then he couldn't hold back, he wound his arms up in her hair and hers cupped his neck. He kissed her passionately now, almost aggressively. She returned his rough kiss, wanting it as much as he did. It was over all to quick and when they broke apart, she sighed and he hugged her close to him, never wanting to let go, let her out of his sight. She rested her head against his chest and closed her eyes.
"Forever?" she said
He stoked her soft curly hair, "hmm...oh, yes, forever."