I’m just starting a promising series (although adult and violent), Gangsta ギャングスタ by Kosuke コースケ. It’s still ongoing in Japan as far as I can tell with 5 volumes and being published in Comic Bunch (Shinchosha) and in English in the US by VIZ Signature.
I seem to find that most of the seinen and shonen manga I read and continue to read – like this by Kosuke コースケ, even in battle manga and other things I’m tired of or wouldn’t normally read, are written by women and often such a different spin that I find it interesting. I wish that many of these women would be able to publish their works in josei or shojo, instead of seinen or shonen; however, josei and shojo just seem to want romance these days (not in the past), leaving great stories written by women mangakas to be published in seinen and shonen magazines that have a wider range (at least seinen mangazines) of subjects to write.
This is totally adult manga and not for the squeamish. This takes place in an alternative reality, Ergastulum, where experimentation, mafia, gangs, police, etc. are involved in murders and turf wars. Several secondary main characters and two main characters, Nic and Worick, who do “clean up”, kind of mercenaries – but not just for anyone (I think – only read the first volume so far so maybe they work for anyone). Both are handicapped and been together for years – Nic is the result of experiment and deaf and Worick seems to lost his eye (and then family) to domestic violence and saved by Nic. Since the story still seems to be setting up and I’m sure there will be new characters; however, it was interesting enough to get past the violence.