I kinda understand how this is legal, if it's lolicon/shotacon hentai, or any hentai depicting girls specifically meant to be underage, even if its not intended as loli (like 17-year-old Nami, 15-year-old Orihime, or 15-year-old post-time-skip Hinata or Sakura, or the apparently 14-year-old chick from Gurren Lagann) would nominally be illegal under these qualifications
It's not quite "right", but i'm pretty sure it's constitutionally sound, so long as its under the basis of artificial depictions of what is legally deemed child pornography

Monster Hunter: pissing me off since 2010.







