KOREAN Seven O'Clock (세븐어클락) Seven O’Clock – Halley Halley “Halley” [EP] Butterfly Effect 2017.03.16 A-Day, Vaan, Hyun, Younghoon, Jeonggyu, Taeyoung Lyrics/작사: CHKmate, J.Fe Composer/작곡: CHKmate, J.Fe, Lody.SYn, Maeel…