You need an embassy visa for Democratic Republic of the Congo if you have a Japanese passport
Visa options for Democratic Republic of the Congo
Visitor visa
Travellers need a visa to visit Democratic Republic of Congo for Business or Tourism. A paper or embassy visa is the only visa available for travellers visiting Democratic Republic of Congo. The visa is typically a stamp or sticker added to the passport. Travellers must obtain this visa from a local embassy, consulate or visa center before travelling.