Underground Comix are pretty graphic 'specially so R Crumb but seems to me they are a completely different animal considering there are scores of other like-minded 60's-70's Underground Pervs...I mean Graphic Artists...that follow R Crumb's muse. Indeed, the whole point of these these Comix (and that is the proper spelling...) was to stick it to The Man/Establishment/Polite Society/Moral Majority by means of outrageous illustrations that point out the many foibles & paradoxes of those aforementioned Middle Class White Americans (or Amerikans, as the Comix would spell it but certainly NOT Muricans as is the current fashion) so while these artists are undoubtedly an influence on Hentai they are not part of it, or even part of modern Western graphic art.