This is exactly why Japan has a (non-legal binding) partnership certification. If those two have a certificate, then it will make their own lives and their agent much more easier. There are so many places in Japan that issue partnership certification, and more importantly, mutually recognize between various issuing local governments, I think once it reaches the point where vast majority of the country's local governments both issue and mutual recognize each other, then civil union will happen. At that point, whether you have a marriage or a civil union, it is the same. It is just which term they would use. The only times when a country has both marriage and civil union, and they have a fundemental difference, it usually means that country has a very strong religious background, ie, church. So if you are a heterosexual couple, you can marry in Italy. But if you are a same sex couple, you take the civil union route. That's why the Pope (at least personally) supports gay couples to have civil union, since the church cannot marry them.
