@Shipmint Just a guess but maybe because the japanese people aren't used to deal with delinquency and crimes, or maybe because they banished the sole idea of killing someone else.
It could explain the rarity of mangas depicting a realist dark society (I exclude the yakuza because they are an exeption, you just have to compare a yakuza with an mexican mob to realize that), and the violence in H games and mangas are really romanticized, even Euphoria or guro is romanticized as fuck.
The only H mangas with a story a bit realist were the ones treating with drugs and women selling their bodies to buy their doses.
But I think Japan need to keep it that way, because too much pessimism or realism could guide them into french art with depressing stories everywhere, as a result their loss of their crazy fantasy or poetry of the beautiful things.
My conclusion is that he (the author) is just bad at writing believable characters.