［DAY6］ 我的天啊超喜歡這次回歸風格 好期待

I'm Serious is a song that expresses the frustration of oneself who can't confess his love. The song will give more relaxed feeling through a more 'vintage rock' sound which is different from the style that DAY6 have showed. It also expresses how the girl doesn't know that the boy has a crush on her.
cr. BusanNerdy