Well, really just bringing in a system they're already familiar with, since promissory notes (like this here) have been used in East Asia for a thousand years, and Japan had decently well-established paper money since at least the 1600s.
Byakuren is doubtless investing the specie for the duration of the period people use her paper money; but what could a Bodhisattva want to invest in?
Is it the anatomy that's off? Or just the perspective? There's something that doesn't add up for me with her neck, and also shoulder/chest alignment in general.
