@Oeconomist @caenlim
If y'all are still at the edge of your seats waiting for an explanation, I did some searching around. It seems to be 爪の垢を煎じて飲む, which is meant to express strong determination to become more like someone, to the extent that you're even willing to take the dirt underneath...
Looks like the artist found a new calligraphy brush instead of trying to replicate the style with the hard round brush.
A step in the right direction, yay
That calligraphy is pretty bad though...
Maybe it's because the artist is trying to Roy Lichtenstein the brush strokes, but it just doesn't look organic at all.