JYJ (제이와이제이) KOREAN Park Yoochun (박유천) JYJ – Thirty (서른…) (Yoochun Solo) 서른… seoreun… “Thirty” JUST US 2014.07.29 Yoochun Lyrics/작사: 박유천 Composer/작곡: 권빈기, 박유천 Arranger/편곡: 권빈기, 황성수