Don't ask me detail!
First you should read this page:
Japan Society for the Promotion of Science
You should contact with a researcher in Japan.
List of set theorist in Japan(including set theoretical topology).
Tsukuba Logic Group(One of Big Logic group)
Tadatoshi MIYAMOTO(Nanzan University)
Osaka Prefecture University
Set theory in Kobe
Information about Japan
THE MATSUMAE INTERNATIONAL FOUNDATION JAPAN