勇民 (Yongmin / 용민 / ゆうみん) is a male given name in both Korean and Japanese, written with the kanji/hanja
勇 ('brave') +
民 ('people'). The trailing
君 (jūn) is the Japanese honorific 'kun' — a familiar form addressed mostly to younger or junior males by superiors, peers, or friends. In Chinese subtitles for J-dramas and anime,
君 is conventionally kept as-is rather than translated, so
勇民君 reads to a Chinese viewer as 'a Japanese-style address to someone named Yongmin'.