One of Sophie's favorite art supples is the Uni Posca Paint Pen. They come in various sizes - which are designed for different uses. In this video Sophie demonstrates the various sizes and suggests how best to use them
The PC-1M Extra Fine is slightly wider than a ball point pen. Best for writing.
The PC-3M Fine point is thicker than than the 1m or a ballpoint but not quite as thick as a Sharpie. Again, best for writing.
The PC-5M Medium Point has approximately the same size nib as a Sharpie marker. Good for drawing and art work.
The PC-8K Chisel Point creates thick solid lines.