At the present time, comics is one of the typical Japanese mass culture, which is supported and inherited by the masses. So, we can know mass consciousness through analysis of comics. Here are four methods of sociological analysis of comics. First is historical analysis of popular comics in each period. To some degree, we can explain why one comic got popular by the situation of period. Second is qualitative method of important comics. It's a kind of intensive analysis of comic content. Third is quantitative method. Researching how many each comic magazine is printed, how often children read comics and so on, we can understand mass consciousness quantitatively. Fourth is analysis of comic writers including lots of semi-professional ones ("doujin-shi" writers) who can be called "mass writers". I select the first method in this paper. Analyzing popular comics historically, I emphasize four characteristics of present comics. 1) Appearance of variety for different readers. 2) Establishment as a media. 3) Publishing very large number of comic books. 4) Vulgarness of content with simple fun, sex and violence.