Hairstylist!au in which Kim Jongin is a back-up dancer for a famous solo idol, Lee Taemin; while having a crush on said idol, soon, he realized that he will never be able to get into the idol's heart being only a back-up dancer and rivaled with Choi Minho, a tall rapper with a baby face who had won Taemin's heart. After witnessing an incident that broke his heart to pieces, Jongin determined to close his heart from anyone. Will he close his heart forever? Or will he let a clumsy yet cute hairstylist make his way into the closed heart soon?