/jp/ - Otaku Culture

Is there a purely Japanese or cross language, relatively international otaku culture or 非リア充-atmosphered forum in existence where a large proportion of the userbase is actually based in Japan?

4chan, 2ch and 2chan aren't cutting it at all but I can't find anything that matches the above. At any rate it seems like people who become fluent in Japanese and makes the move end up not posting so much here which makes me wonder where they end up.