Prismacolor sepia pencil, A5 paper. I'm trying to capture her expression of looking intently at something, or trying to figure something out. I think it is all in the tilt of the head, the compressing of the neck, and the posture. I think when someone is concentrating on something very intently, their eyes might be closed slightly, but their jaw is relaxed and loose (which is shown by it being a fraction forward, and probably a fraction less shaded, depending on which direction the light is coming from).
A quick miniature sketch of a guy looking out a window to try out my new Conte Pierre Noire and Prismacolor colorless blending pencils.