Defectors from North Korea are also considered South Koreans in the West

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It is not just the Republic of Korea alone
that views its territory as the entire Korean Peninsula and its adjacent islands and considers North Koreans to be South Korean citizens;
the free world nations, such as the US, Japan, and European countries, also view North Koreans as South Koreans,
so if they request help, they connect them to an embassy or consulate.
UK High Court Ruling
https://www.bailii.org/uk/cases/UKUT/IAC/2014/%5B2014%5D_UKUT_391_iac.html
(3) All North Korean citizens are also citizens of South Korea.