Guest post by "Z" I agree that it doesn't really work in the second panel. I don't know if it's the panel, or what. It can be quite pretty and add depth. Maybe if the lines were darker it would work better. I also find that it gives a softer look to the piece, which doesn't really mesh with Sarah's freaked out expression. It would add to the more upbeat and light-hearted strips, but here it contrasts with the tone of the strip.
I think that the different line colors work in the other panels, though. It works really well for the first and third panels because it adds to how deflated Sarah works, in the final panel- it might be better to have it a little darker because Lucy is still an imposing figure and it seems a little conflicting to have her greyed out like that given her pose. Obviously this is a lot more work and it'll take time to work out how to do it properly, so if you don't have the time for it, I'm sure everyone understands. It looks fine with all black lines.
A+ to Lucy for getting straight to the root of the problem. And good that Sarah realizes that this isn't a good situation, even if she doesn't want to admit it to herself. This friendship isn't totally doomed, but things really need to change. I don't think either girl sees the other as a full person to be friends with.
