방탄소년단 데뷔 싱글 -2 COOL 4 SKOOL- 6월 12일 발매BTS Debut single -2 COOL 4 SKOOL- will be released on 12.JuneOfficial Homepage : http://bts.ibighit.comBTS Blog : http://btsblog.ibighit.comOfficial Facebook : https://www.facebook.com/bangtan.officialOfficial twitter : https://twitter.com/bts_bighitiTunes : https://itunes.apple.com/us/album/2-cool-4-skool/id660164564