Real name: Yoo Youngdoo , but he legally changed it to Yoo Jiahn (유지안
Born 1992176 cm♈ Aries
As the main vocalist of Unit Black, one of the units formed through the Mnet survival program *BOYS24*, Youngdoo — born Yoo Youngdoo on April 1, 1992, and later known legally as Yoo Jiahn — built his early public profile within the competitive structure of that 2016 idol-development format. Unit Black represented one of several rotating lineups produced by the program, with Youngdoo serving in the lead vocal role that defined his position within the group.
Beyond his time with Unit Black, the available record of his solo activities and subsequent career remains limited in documented detail.
