Just a quick comment: as I noted in my other post it is normal for companies to give 20 days of sick leave. Often you can't take them, though ;-) I don't know a single person working as an employee of a large company in Japan that doesn't get 20 days of sick leave. But those stresses are very important. Most foreigners do not get permanent jobs and are not employees. They are contract workers, who get no sick leave. The number of contract workers in Japan is growing, though.