I thought at first that it was a spider leg in my dream, too, or some kind of tentacle hovering in the foreground. But on my most recent playthrough, I saw a pair of boots next to my sleeping PC, like someone was standing right there, but facing away from her. Like a foot from her. And I think that the thing I first believed to be a leg or tentacle is the outer edge of a wingtip, since it looks to be about the right distance from where the figure is standing. Again, I could be totally wrong, but that's what I think I'm seeing. At least it will be fun to figure it out over time.
