There’s a handful of “underground” manga in English, most of it fairly interesting. I’ve always hated the designation “underground manga” since it feels like a marketing term, but it’s a neat category for any book that doesn’t fit in with the genre and age group tropes you find in most manga. Yoshihiro Tatsumi is probably the most widely-read and has the largest body of work available in English. There’s also a handful of books by artists like Yusaku Hanakuma (Tokyo Zombie), Imiri Sakabashira (The Box Man), Seiichi Hayashi (Red-Colored Elegy), and Yuichi Yokoyama (Travel). Those artists all range from thematically and visually similar to Yoshihiro Tatsumi to… much more out there, to say the least. But one of the most infamous is Suehiro Maruo. He is first and foremost a fantastic illustrator. Favoring the time period from 1910-1930, his work usually has a modern antique feel to the settings, clothing, and characters. He has a very stiff, ornate drawing style that is clearly inspired by Japanese ukiyo-e work, but the period flourishes and accurate figure drawing make it feel very western. But most people walk away from his books remembering the outlandish but beautifully-rendered violence. Violence so intense, in fact, that I had trouble finding a good example for the header that wasn’t too gross to put above a cut. Because he is an illustrator first, his comics don’t flow that well, but his panels are frequently interrupted by bizarre, very shocking tableau.
Only three volumes of his work have been translated into English. I mention them all here, mainly because The Strange Tale of Panorama Island came out a couple weeks ago, and it’s worth reading. For the curious, there’s also a Maruo short story in the collection Comics Underground Japan called “Planet of the Jap,” a bleak and violent what-if story about Japan winning WWII that is not for the faint of heart.