"Riki-Oh" is a manga that's definitely out there in terms of its storytelling and content. Published from 1988-1990 in twelve volumes, it chronicles the journey of the titular Saiga Riki-Oh on a larger goal, which isn't revealed during the earlier chapters. At first, we see him transferring into a Tokyo State Prison at the age of 21 to serve the rest of his three year sentence. He's got incredible physique and strength, with infamy surrounding his name. The prison he's serving his time in is awful, led with a corrupt administration and overgrown bullies that enable or partake in undeserved brutality against many of theprisoners, who are incapable of fighting back. But our protagonist's heart equals his strength, so he makes it his mission to free the prisoners from the horror they face. Riki-Oh also discovers just how to accomplish his goal, which is something that'll carry the manga forward.

This also contains many battles that focus on graphic violence and over-the-top fighting, similar to "Fist of The North Star". Tetsuya Saruwatari's illustrations are generally great, though some panels and background characters look wonky. Takajou Masahiko's story is more uneven: the first arc within the prison is engaging but already a bit nutty. Then, once the story leaves the Tokyo State Prison, matters get much wilder. The twists (they get appalling toward the end), violent fights, story beats -- ALL get considerably more over-the-top. And, mind you, there are already some out-there moments in the first 13 chapters: an example including a younger guard being told that Riki has seven bullets stuck inside his chest!

I would say that if you can stomach a manga just being really strange, and enjoyed masculine focused stories like the aforementioned "Fist of The North Star", then enjoyment can be found with "Riki-Oh". I enjoyed it myself, but you may not apply. And I wouldn't blame you: this manga's unconventional nature isn't for everyone, and that should be considered prior to reading it.