How to create tone with pen and wash
Draw your picture using a water-soluble ink pen. Here I am using a fine liner, but you could just as easily use a fountain pen.
Now dip your brush into clean water and wash over any of the lines and into any areas that you want to shade. The brush will dissolve and pick up some of the ink to create a shaded wash.
This little sketch show what can be achieved with this method.
Click on the picture for a larger image.