Sending belongings to Japan, what do I have to write on the customs invoice as the reason for export, and do I have to pay any kind of tax for this when I pick up the package in Japan?

Pretty much as the title says, I’m moving from Norway to Japan in April, and I want to send some belongings I can’t fit into my suitcase to Japan beforehand. What would I write on the documents, and would I have to pay taxes for picking up my own belongings while in Japan?

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Norway is pretty anal on this kinda stuff, have to pay import tax on most stuff – even gifts, so I want to know what I get into before I actually send my stuff over there.