K. Ze Scoop.
The bass is awesome. Don't change it. D: It rocks.
Now, for the melody. It sounds really good, but in my opinion, it's a bit repetitive, and the fact that there wasn't a build-up until 2 minutes into the song, which led back into the same melody, makes it a bit dry.
I understand it's a demo. It's going to be really good I can tell! Just mess around with the melody some and change it up.
Good luck!