Dude. That's awesome! Amelia rocks, I love her.

...wow... you certainly got to the action quickly. I'm liking this.
We have a mysterious possession of Nigel's that the bad guys want, and the bad guys seem to be more than human if they can "smell" Nigel inside the house.

Awesome.

:D CD

...-blink- whoa!

That's a change. From magic to mystery in a moment.

Ooh, who IS that guy? Is he the demon of the title? Somehow I doubt Debt is the demon. And there I go alliterating again. Sorry. Anyway, interesting story, a few grammatical typoes but nothing to get snooty about; a quick check and you'll probably find them on your own.

I await more!

:D CD

The relationship between Debt and Amelia is fun and best of all, believable. The dialogue is mostly well done, if sometimes rushed or, in the case of a few explanations, hard to understand. For example, why do combined objects explode if separated simultaneously?

Can't wait to see what's up with the guy floating down the stream...

It seems too short, even for a prologue, but that's not much of a detracting point. The first sentence starts out good, but stumbles, in spite of (or perhaps because of) the description. It's very good description, but it would benefit from being drawn out into more than one sentence.

The rest is great! I like that you left out names and kept to a very vague presentation, perfect for a prologue. However, in most quick exchanges, it flows better if you occasionally leave out tags like "he said" and "she muttered". Dialogue doesn't always demand that you state someone said it.

Thought opening sentences a little too long and could have been broken up. Instead of simply stating how things were at times, try to describe and explain them.
It's pretty short - and perhaps you have a concept but it's not driven out as much - perhaps a bit more exposure on the topic. And it sort of only brings out a very subtle hint of idea and nothing more. It's also missing things like what the story will be about etc, ...
Anyhow. Cheers.