[quote=@Lord Orgasmo]
Are we all Japanese, or are just from anywhere and we all are going to conveniently meet up in the digital world 
[/quote]
Well I dont see any reason why we would have to all be from Japan.  Though there is the benefit from all coming from a single region.

At the risk of sounding too amerocentric, please forgive me;
We all speak english, the USA is a very large country separated by many different climates and sub cultures yet united enough through news and communication to remain homogeneous. I think the majority of us should probably be from the USA for those reasons. It leaves us plenty of variety to work with, including the past of immigration in the US so if anyone wants to bring their culture into the character that'd work well. 

Though this of course isnt like a huge deal. If your character can speak and relate to the other kids thats fine.