Kumamoto ranked relatively highly (10th) among Japan’s prefectures for the percentage of women in executive positions. However, that may not be all that much to brag about because the numbers for Japan as a whole are still pretty low. If you read Japanese, you can find the report by the organization that published the survey here:
http://www.tdb.co.jp/report/watching/press/p140804.html
The graph (taken from the Japanese press release, not the English article) indicates that female representation in managerial positions tends to be much lower in Japan than representation in the “employee” ranks.
http://www.japanupdate.com/2014/08/okinawa-women-score-high-as-business-leaders/