[ The longer Amos looks at them, the stranger they seem. They simply don’t seem to reflect the light in a way that seems correct, smoothing out all detail of what they cover. Like vantablack, it’s almost confusing to look at. But of course, Sebastian just nods and laughs as pleasantly as if this were something normal. ]

In a sense. They are shadows, yes, but they are a bit more than that as well. It is more accurate to call them a part of me. They are far closer to what I truly am than this appearance, but it is much more convenient to take a human shape when I am visiting. Likely more polite as well!

[ Since the real one is, uh, a lot! To answer his questions in part, the shadows around the glass shift to form a dark, clawed hand around the glass that solidifies into something much more solid and real-looking, though it’s still held aloft by tendrils of the odd shadows. ]

And I can use them to create, yes. Pillows included. They are something I am able to form like clay into whatever I'd like. Well, within reason, at least. It has to be something I know very well, and I cannot create especially large or living things, but it is handy all the same.