First off YAY! that is so cool, I hope that you post updates on how your trip goes, I would look forward to hearing more about your experiences in Japan.
I have an aunty who lived and taught English there for 10 years and she loved it.
I often fantasize about what it would be like to live another life as a white collar in the city, going about day-to-day life in the Hussle and Bussle of city life.
I am sure I am just romanticizing a warm nostalgic feeling associated to the image I hold in my head and that reality is much different but I kind of find a comfort in it all the same.