She was the first person to notice there was something going on. Everyone else was so insistent on believing that Harry and Ron were just good friends that they couldn't see what was right in front of them.
She noticed, when they were sitting in the common room, amidst all the chatter, how their eyes would meet and the look would last for a fraction of a second longer than normal. There was intensity and heat and passion, captured in that moment, and she felt that if she reached out she could touch it. But she never moved during one of these moments. She was frozen, not wanting to disturb this thing, whatever it was, so fragile and fleeting.
It hurt. Just a little. Enough to cry herself to sleep for a few nights, and then get it out of her system. Because as time went on, and other people started noticing, and Draco made some snide remarks as he always did, and they worked up the courage to make small gestures in public, like holding hands, she realised that she could pretend it was her red hair that Harry touched, her skin being caressed. And that - well, that was almost enough.