But Allison doesn't know that. Doesn't know where Dean's morals are, what his thought process is. All she sees are the facts, and those facts are that he kills people for a living. People who he did not have the right to decide if they lived or died. He isn't even Dean, from what she knows. Just The Reaper, a hired gun, a villain.

The angry part of her that spurred on the sprint in the first place revels in his expression. She caught those wide eyes, that oh shit, and it has her grinning a little. Yeah, you better run. And she'll just keep running right after him, having gained a lot of ground due to the few seconds it took for him to react. It's not close enough to catch him, but it's close enough to keep up with him, considering how thick the crowds are in this area of the city. Allison does her best to dodge through the people, to follow the stream the Reaper leaves behind him when he shoves through the bodies of the crowd.

It's mostly because of the people that she doesn't know what he's doing at first- just keeping her attention on keeping up and not losing him in the crowd. It's not until there's a certain break in the crowd that she sees him tear off another piece of his clothing, turning his head enough that she sees his mask gone, sees the cut of his jaw, his eyes, the whole thing. Just a flash, sure, but she's been trained since birth to recognize a man with less. That? Right there? Signed his arrest warrant.

She doesn't recognize him, but that doesn't mean she won't be able to find him, later. But then, like the crowd is making up for that brief opening shot, it thickens between them and she momentarily loses sight of him- needing to take a moment too long to push through the throngs of people and come out on the other side.