When you look at a drawing, you can usually identify if it was drawn with pencils.  This is probably due to the unique colors and strokes of the graphite lead. A typical example is a pencil sketch.

These blocks have the texture of a pencil drawing.

The pencil sketches are not used on ordinary products as CMF, therefore the fresh expression gives us a strange sensation as if the pencil sketches have become three-dimensional objects as they are. 

The fact that the stroke marks and textures that we usually see in drawings exist in a three-dimensional form gives us a waver in our sensation.

The block shape is like a drawing when seen alone, but when assembled, the shape becomes more like a motif of sketching. The wonder of the actual existence of what we have seen in drawings nurtures our sensitivity to the existence of things that we humans have originally possessed.