>>thunde+(OP)
Japan is insane on the paperwork front. The amount of stuff my wife has to deal with (because my Japanese is frankly terrible) for basic processes is mind numbing. Things like having to write out your address and contact info on five different forms for one appointment, visiting multiple offices to submit paperwork in for the same process, etc.. Moving apartments (heaven forbid it is to a different city government) involves weeks of straight up administrative work from one person in the household.
>>Lehere+kq
For the purposes of government ID, you're going to have a principal residence. But, for ordinary people, there's no real guarantee that you actually live there. It could be a friend's house who keeps an eye out for important mail.