Say Campus Notebook in Japan and everyone knows what you are talking about. The notebooks are really everywhere and available in a large variety of formats and rulings, and are widely used by students and office workers. We at Mofelito discovered them on our first trip to Japan years ago and we now start selling a very small selection. Let's see how you all like them.
Graph paper seems to be rather hard but Kokuyo has it so we stocked on pads in A5 and B5.