I don't know about that lol
There are plenty of white man and white girl (feeling kind of weird to say this by the way) live in Japan, some works in multi-national business, some work as an English teacher in Japan and also not to forget there are a large American present in Naval and Air Base in Japan, he could be one of the deployed personnel, family of the deployed personnel or contractor.
Think it is up to individual who think why they want to live in one place, I am not him so I cannot tell you why he wanted to or claim he wanted to.
My MPhil is going nicely, I have abandoned the Economic program in Melbourne and enrolled in School of Strategic Studies from ANU (yes, it is actually what it called, I laugh for a few week having classes in the ANU) The Research Advisor I have in Melbourne is shit, I wished I have got into the MPhil in Computer Science, anyway, ANU program is the one that I can make before cut off (Censor) date, so I am kind of stuck at this moment.
I am currently at my final stage of my MPhil Thesis, should be able to make it in July deadline.