I looked at some Japanese news coverage and apparently it wasn't any specific sexual nastiness that got him in trouble. It seems he ran afoul of the censorship laws by having explicit, unobscured illustrations of genitals in his work--still officially a no no in Japanese erotica. According to the judge: "Bodies were drawn in a lifelike manner with little attention to concealment (of genitalia), making for sexually explicit expression and deeming the book pornographic matter," Nakatani said as he convicted Kishi" Schoolgirls being ravished by tentacle monsters is still OK as long as you don't show the goodies.

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken