On Instagram, CL wrote that last year at this time, she promised herself that she would release new music in 2017. As a gift to her fans, she shared a teaser to an unreleased music video that she filmed over a year ago. CL added that she decided to release the teaser video even though she might get in trouble for it.
From the teaser, the song sounds so good, I don't know why this was never released. Check out the teaser below and let's hope for an official release soon.