Bolbbalgan4.

K-Pop

BOL4, also called Bolbbalgan4 (볼빨간 사춘기) is currently a South Korean soloist under SHOFAR Music. BOL4 started as a duo, also called ‘ Blushing Youth ‘. Additional background says that The duo consisted of Jiyoung and Jiyun. The profile also notes that they both participated on Superstar K6 in 2014. The duo officially began activities on April 22, 2016. On April 2, 2020 Jiyun departed the group, and Jiyoung will now promote using the name BOL4 as a soloist.