got it right.
The titular character is practically retarded and can only get sexual relief after murdering people, so yeah, he cries while masturbating on their remains. He was sexually traumatized when he helped a gang of boys rape a girl, he doesn't fuck her, but he goes fucking crazy and is convinced she wanted him to rape him.
The other guy is a complete S&M freak who kills a guy by firing a gun up his asshole, gets off on the idea of his own death and that Ichi might kill him.
That's just two of the main characters, everyone else is pretty much at that level of crazy though.