unless you speak japanese and are around them for more than a few minutes I would give up now
As attractive as they are J-girls are usually in a big group and hard to get away from said group. If they are up for some 'fun' they often go for the 'rough' thai beach boys.
Easier option is to find a thai that looks japanese - quite a few about.
....hey a whole post about J-girls without mentioning tentacle r4pe.....
DOH!!!