In 2015, he sang 머리핀 (Hairpin) for the OST of drama Romance for 7 Days, a collaboration drama between Korea's CMB and Hong Kong's TVB.
Pada tahun 2015, ia menyanyikan lagu 머리핀 (Hairpin) untuk OST drama Romance for 7 Days, suatu kolaborasi antara CMB Korea dan TVB Hong Kong.