marriage and visa

I recently asked my Japanese girlfriend to marry me, and she said 'yes'. I live in a European country. She lives in Japan. Because she currently has a better job than I do, we decided it's best if I move to Japan (for now at least). So now we're trying to figure out all the formalities we have to take care of, but there are many things that aren't exactly clear. Some questions:
Can I go to Japan on a 90 day temporary visitor visa and then get married? And after marriage, apply for a spouse visa? Or do I need another visa to enter Japan in this case?
Of course, we already know about the special documents I need to get married in Japan, but what other formalities are there we need to deal with? Is there anyone in these forums with some experience in / knowledge of these matters?
Any information and/or advise would be highly appreciated.

Can I go to Japan on a 90 day temporary visitor visa and then get married?

Yes.

And after marriage, apply for a spouse visa?

Yes. But it is possible that the process takes more than 90 days, in which case you have to leave Japan once.

Or do I need another visa to enter Japan in this case?

No, it is possible to apply from within Japan. First you have to get a certificate of eligibility and then you will have to change your status of residence from "temporary visitor" to "spouse".

Thanks for the quick reply.

Yes. But it is possible that the process takes more than 90 days, in which case you have to leave Japan once.
For how long would I have to leave? Until the process is finished? Or could I come back on a new 90-day visa after a certain amount of time? And in the latter case, what would that 'certain amount of time' be?

For how long would I have to leave?

It can be as little as a few hours, by going to Korea and back. The shorter, the more suspicious (immigration might suspect illegal work).

Or could I come back on a new 90-day visa after a certain amount of time?

The process is very unlikely to take more than 6 months.

Uji, are you sure about that? When he applies to change his status of residence he should receive a stamp in his passport with a date and application number. As long as he has this stamp, he should be able to stay until his application is approved/denied. It's best for him to ask the immigration office to confirm.

When he applies to change his status of residence he should receive a stamp in his passport with a date and application number. As long as he has this stamp, he should be able to stay until his application is approved/denied.

That's right. Once the application for residence change has been submitted, he actually would even be required to stay in Japan (passport is among the documents submitted to the authorities). But this part of the process usually takes only a week or two.

I was thinking about the waiting time for the certificate of eligibility (which needs to be processed before the actual application for change of residence can be made), which is usually the part of the process that takes the most time. Typically three weeks to three months. If your visa expires while waiting for your certificate of eligibility, then you would have to leave Japan once.

Summarized:

In case of expiry while waiting for certificate of eligibility (typically within 3 months): must leave Japan

In case of expiry while waiting for change of status of residence (typically within 2 weeks): must not leave Japan

Thanks for clearing that up. I didn't know a certificate of eligibility was required to change status of residence.

It is actually possible to have your fiance take care of all of the appropriate paperwork in Japan, including the marriage application, in advance. This will require mailing a few items back and forth. From your home country, you can apply for a spouse visa from the local Japanese Consulate and your spouse visa could be available within a week (this is apparently faster). So, you could have a spouse visa before the ceremony in Japan (if there is one). At least, that is how it worked with me.

I forgot to mention that the process might have been streamlined for me because we were first married in my home country, and could produce a valid marriage certificate from my home country. I can't remember if this was important or not. The required documentation is constantly changing...