Soyou

Soyou is the most commercially successful Korean female solo artist in the traditional ballad-duet format, with her Sistar subunit and collaborations surpassing one billion streams on Korean platforms. Her 2017 duet with Jung Gi-go, 'Some,' sold over 2.5 million digital copies in South Korea alone, outpacing #10 BoA's peak single performance from the same era. Notably, her collaborations with Loco and others dominated Korean digital charts throughout the mid-2010s, achieving faster chart climbs than the average female solo release. This data-led dominance cements her as the ultimate ballad collaborator in K-pop.