Soulstar have mastered softly sung yet overwhelming heartbreak tracks since 2005. It's a subject matter familiar to everyone, but the trio—who throw a little urban pop into their K-pop mix —write songs that feel realer than others. Despite the pulsing midtempo beats and slick vocal harmonies they employ, the authenticity of emotion that inspires the likes of "Rainy Street" and “Unbelievable” is undeniable, marking Soulstar as K-pop's champions of tear-inducing heartache.