It's odd and I know it, and I rather like it that way.
Themes used were depression, sparks and finder's keepers.
He was there first.
"Finder's keepers," he said, with that smirk that you hated so much. How could he be so arrogant, so cocky, so sure of himself? You doubted everything, everything about yourself. Sometimes you even doubted that you existed, on those lonely nights when the atmosphere was nothing but depression, collapsing in on you and pressing you down.
He always took what you wanted, too. It didn't matter what, but you were so alike, you always wanted the same things. And he always got them (never you). So what did you do?
You retreated. The depression pressed harder against you then, stealing away the last vestiges of feeling until you thought that everything was the same dull shade of grey. Not a real life, but something less than that.
And of course, it would be him that stole that away from you, too, frightening you for perhaps the first time since you were a tiny, tiny child. You had to go after him (though you'd never tell anyone that it was more than a simple mission to you) and save him. You didn't really know why, except that maybe, maybe it should have been you instead; you who didn't deserve a real life, but a half life lived in the shadow of a sorceress.
But he took even that idea from you, standing there, laughing, arrogant, perfectly all there, a sorceress's knight who almost outshone his sorceress. He was beautiful, and it was then you found love; you loved him with a little ache that you knew meant the darkness couldn't touch you anymore. He'd probably take that away from you, leaving you with nothing (that thought made you angry for some reason; you didn't want that), so you kept fighting, even though he was probably happy where he was, though that place suited him, like it was tailor made for him (like everything was, everything was his anyway).
When it was all over, the little (stubborn) spark of love for your (even more stubborn) rival didn't go away. You didn't know how to deal with that, so you went to him, to tell him (to confess; it felt like a guilty secret then).
He didn't take it away (it felt more like sharing it than confessing and having him take it away). He gave you the oddest look (and still looked good doing it) and then he kissed you.