S.M. Entertainment’s SM Station project is a weekly digital-single series encouraging the label’s artists to explore genres outside their comfort zone. In the case of SUHO—leader of the K-pop boy band EXO—that means delving into understated neo-soul with “Curtain,” a tender, heartbroken ballad centered around his delicate vocals. The only accompaniment to his singing comes courtesy of jazz pianist Youngjoo Song, who provides an emotionally resonant backdrop to amplify the warmth in SUHO’s voice. The instrumental B-side version lets you appreciate her deft playing all the more.