Japanese cartoons and comic books are full of weird porn, as you may have noticed. A bill in Tokyo to tighten restrictions on sex in manga and anime is expected to pass today, barring publishers from selling material depicting "sexual or pseudosexual acts that would be illegal in real life or sexual or pseudosexual acts between close relatives whose marriage would be illegal."
This is interesting because Japanese porn is full of what you might call "pseudosexual acts" that wouldn't just be illegal but probably impossible in real life. Many of same, like the notorious "shokushu goukan" or tentacle porn, were conceived to get around censorship rules that prevented the depiction of genitals. (See also "omorashi," or "bladder desperation" movies, in which women who've drunk a lot of water try not to pee. There are omorashi game shows.) It's almost like a psychological case study of how sexual repression creates strange and interesting fetishes — just, in this instance, played out on a national instead of personal scale.
The bill suggests that fetish anime and manga "could inhibit the healthy development of youth," which is probably true if you define "healthy" as "non-fetishistic." Needless to say, anime fans and producers are not happy, with ten publishing companies boycotting the upcoming Tokyo International Anime Fair. If this new batch of restrictions passes, just imagine how inventive fetishes will have to become in the greater Tokyo area.