Maybe for mean time it is for Japan only but since this is a new technology for gambling and the demand will surely increase?
I don't know, if the demand increases, it means that innovation involving anime characters is very popular among gamblers especially those who like slot machines, but so far this has not happened. the possibility of innovation involving anime characters will only be in Japan.
then it will be spread for the whole world mate, we knew how big the gambling business all over the world and when you find this profitable and in demand then why not gambling owner will not invest on it?
so it will be for the world in the future.
however, without involving anime characters, slot machine gambling will still be loved all over the world.
so this does not necessarily attract the attention of land or online casino owners, especially for slot game developers themselves such as pragmatic for example.
they won't invest in something that doesn't have a high response from their customers, until the day it does.