Although Alice had warned him in no uncertain terms to stay away, he couldn't resist watching her. And the fact that Alice had known what he would do only confirmed he would do it, that he would ignore advice because his mind was already made up. Alice's power worked based on decisions that were already made, courses of action that had already been decided. Of course, those visions changed when the person in question changed their mind, but some never changed. Some were pre-destined.
Edward watched her raise her arm and bring the stake swiftly down, dusting the vampire she'd been fighting. She dusted her hands off and glanced around, tilting her head slightly, and he lowered into a crouch, eyes never leaving her face.
The wind blew faintly, the long brown hair shifting slightly, and Edward's nostrils twitched, the new scent invading them. His eyes darkened to black, the purple colouring underneath his eyes becoming more prominent.
This is why Alice had warned him off. This was the exact reason.
For the first time in over seventy years, he wanted to feed off a human.