Happiness! Hello, I'm Joy! Park Sooyoung (Hangul:박수영) also known as Joy, is a South Korean singer and actress. Joy auditioned and was cast by SM Entertainment at SM Global Audition in Seoul in 2012. She trained for two years during which time a vocal coach gave her the stage name "Joy". Joy was introduced as the fourth member of Red Velvet on July 29, 2014. Red Velvet made their debut with "Happiness" on August 1, 2014.