Kim Na-young (born December 31, 1991) is a South Korean singer who gained immense popularity through social media exposure on New Year's Eve 2015, when her single "What If It Was Going" topped the MelOn music charts of South Korea's biggest music streaming site, holding the top place for five days, and high spots on other streaming sites. She has recorded several soundtracks, including "Once Again" for Descendants of the Sun. Music career She debuted as a singer in 2012, after which she took the unusual route of busking in the Hongdae area, where a video clip of her singing on a cold winter night went viral and attracted over 1 million views. She had a few TV appearances and was a contestant on Mnet's Superstar K in 2013, but did not reach the finals. Due to that exposure, her singing skills were noticed in the K-pop industry and she did a 2014 original soundtrack for a Korean drama. New Year's Eve 2015 viral success Her sudden rise in popularity, without being known much by mainstream media, occurred with the release of the viral video clip "What If It Was Going" and was called remarkable. Social media experts said the video's reception, which "spread like wildfire among young trendsetters," was because "mobile oriented social networks are changing the traditional routes to success for singers." She called the success, which coincided on her birthday, December 31, an unforgettable birthday gift. Descendants of the Sun OST She has recorded a number of soundtracks, including those for The Girl Who Sees Smells, Orange Marmalade and Bubble Gum. In March 2016, she and Mad Clown collaborated for a well received OST "Once Again" for Descendants of the Sun, and used as background music when the drama’s leading roles flashed back to old memories.