1. An image forming apparatus that forms a first image in an image region of printing paper and forms a second image in a non-image region of the printing paper that is outside the image region, said image forming apparatus comprising: an enlargement/reduction ratio specification unit that enables an enlargement/reduction ratio to be specified for the second image; and an image forming unit that forms the first image in the image region of the printing paper without enlarging/reducing the first image and forms the second image and the non-image region on the printing paper after enlarging/reducing the second image and the non-image region by the enlargement/reduction ratio specified through the enlargement/reduction ratio specification unit.