While manga is now a well known entity in the global publishing scene, the medium's international success has its roots in the realm of eros. Japanese media critic Kimi Rito dives into the history of manga's erotic world a genre known internationally simply as - hentai. What are the origins of hentai? How has it evolved from the days of ukiyo-e to today's modern comics and animation. Who are the people making hentai? And who are the people reading these works? And what is the medium ultimately trying to express beyond sexuality? Rito looks at the content from a number of perspectives covering everything from the indie comics scene (doujinshi) to how hentai's symbolism has extended far beyond Japan and its comics industry.