What is illustration 6

Through this image I am questioning what illustration is by comparing two different drawing techniques and combining them to form a singular image, each which lends a different perspective on the subject. For example, the charcoal gives a dramatic effect with gently shading and an overall subtle feel, where as the pen gives a more sketchy effect and a rougher feel to the hands. These different techniques show that an illustration can be a response to the medium used, to create a different view point on the world.