The geometric relationships between the nostril and the shadows in the ear are really interesting in terms of the visual conversation in this portrait. But the reason for me that the picture works is that it makes you wonder what he thinks about his profile when he himself, of course, can't ever see it in action.
Kind of reminds me of my former photography instructor. Great work on this series. I don't know what others think of it, but I can see how it might be overlooked. I really appreaciate your choice of colors and lighting.