In general, I am talking about AVN precisely as a work of art, such as books, games and films, where the elaborated world, both from the point of view of history and graphics is the basis, not a secondary factor (or not necessary at all), and the porn part is just an addition. It seems to me that due to the presence of the above factors, porn parody are extremely popular with many players and do not require much effort from developers. Maybe you're right, and things like the background don't make sense for most players, but in this case there are a lot of classic porn with and without a plot and the meaning of these VN disappears, since they don't give anything new, no zest, especially considering that most are kinetic.