[Sangetsu]

It's not as easy as simply getting married. First of all, you may need to show some kind of proof that your relationship has been going on for some time. Usually letters with dated postmarks are used for this. Also, most people get married after more than one visit, so travel tickets for previous visits could be used. You'll also need to provide an affidavit from the government of your country proving that you are not already married to someone else in your country, and you'll have to get this affidavit translated into Japanese.

But wait, that's not all. Before you'll be granted a spouse visa, your girlfriend will have to show that she earns enough money to support the both of you. If she is a student, or has only a part-time job, this will not be possible. In this case, you may have to get her family to sponsor you, provided that they make enough money to support both you and her.

The only other option is to like others do and get a proper work visa. For this you'll need a 4 year or better university degree, and sponsorship from a company who is willing to hire you.