The Brief: A "bias" in Korean popular culture is a fan's favorite group member.

DEEP DIVE
A “bias” in K-pop is an individual’s favorite member of a K-pop group. The word is based on fans favoring or being “biased” towards a specific member.
“Bias group” refers to your favorite K-pop group.
johnny would be the guy to say "yo dude c'mon knock it off" if your boyfriend is an ass to you at the party and that's why he's my bias
— johnny seoft (@taeyongseo) August 4, 2020
yeosang is suddenly my bias pic.twitter.com/SufGhEIZRN
— β‘ gio β (@ouchsannie) August 6, 2020