'Superstar K4's Hong Dae Kwang has joined�SISTAR's Soyu for a duet!

This duet, which is called "Good Bye", is a part of Hong Dae Kwang's debut album coming up on the 19th, but it has been released earlier as a pre-release.

"Good Bye" has not only been written by the singer, but composed by him as well and with the emotional vocals of Soyu joining the song, it should definitely capture the hearts of music fans who love a slower-paced song.

Check out the song below!