Does Gossick Suva really exist?

There is no such thing. It's a country made up by the author Sakuraya Ichiki.

In fact, it can be seen from the plot that several countries, led by Britain and Suva, became the victors of World War I, but if you look up World War I, you will find that there is no Suva at all.

Here are some references I found. In a word, Suva is a beautiful and mysterious country, but it does not exist.

The name of Suva Kingdom is a homonym. In fact, it is the Loire, the largest river in France. The country of Suva should be the Loire Valley.

The name of the kingdom of Salem is also true and dissonant, and only the first half is used.

Saint Margaret College is actually a four-star hotel in Saint Margaret, France, and it is also near the Suval River.

Victorique de blois's surname is bulova, and there is a Beaufort on the Loire River. Maybe the author thinks it's a good name. . .

The description in the novels of Suva Kingdom is fictitious. Probably located between France, Switzerland and Italy. These can be seen in Wikipedia and other places. It should be that the author traveled in the Loire Valley in France and used some other nouns nearby. If you have time to search, it should all be related to it.

Here are some references I found. In a word, Suva is a beautiful and mysterious country, but it does not exist.