So it's been commented that the nightstalker style is very loose and sketchy.
For the most part it consists of rough pencils, coloured, but not inked. It can and does look rough but that's part of it' charm. Do not mistake style for ability. I deliberately adopt the style to get pages out faster. Occassionally I experiment and use ink. When I do so it's because I'm trying something out to get a better balance between speed and quality.