He already sang "I Couldn't Cry Because I'm a Man" for part 1 of the OST, and he'll be lending his voice to the drama again through Part 7, titled "Tree".
"Tree" is Yoseob's self-composed song, co-working with Gyuberlake. He participated in writing the lyrics, composing, and producing the song.
Check out the teaser for the OST above! The full track will be out June 7 at 6PM KST.