Many of Maruo's illustrations depict graphic sex and violence and are therefore referred to as contemporary muzan-e (a subset of Japanese ukiyo-e depicting violence or other atrocities.) Maruo himself featured in a 1988 book on the subject with fellow artist Kazuichi Hanawa entitled Bloody Ukiyo-e (江戸昭和競作無惨絵英名二十八衆句), presenting their own contemporary works alongside the traditional prints of Yoshitoshi and Yoshiku.