Songs with Korean Titles must be romanised by using the "Revised Romanization of Korean" released to the public on July 7, 2000, by South Korea's Ministry of Culture and Tourism in Proclamation No. 2000-8. Loan words should be expressed using romanisation from the original language.
Something pretty obvious that should exist considering rules for Chinese and Japanese are already stated.Cases such as https://osu.ppy.sh/s/315307 which is obviously wrong in metadata but having no reason to DQ since there were no related RC should not happen anymore.