A great lil drinking game is to go onto the
Visual Novel Database and see how many "VNs" are just hardcore porn or highly specific and fucked up niche fetishes
Sturgeon's law applies hard, i think the main reason is that VNs are easier to distribute than doujinshi and other shit like that, iirc there was also a japanese law loophole that made it so PC games didnt need a CERO rating, so everything thats a nono besides uncensored genitals is free game for any degenerate that who can cobble a VN together