MustB (머스트비) is a five-member boy group under MustM Entertainment. They held their debut showcase on January 21, 2019 and released their first single "I Want U" on January 30.
|Sihoo (시후)||Lead vocalist, main dancer, maknae||Purple||2019–present|
|Taegeon (태건)||Main rapper||Blue||2019–present|
|Soohyun (수현)||Vocalist, lead rapper||Orange||2019–present|
|Doha (도하)||Main vocalist||Green||2019–present|
|Wooyeon (우연)||Lead vocalist||Indigo||2019–present|
|Sangwoo (상우)||Leader, rapper, vocalist||Red||2019|
- Let Me Rise Again (2020)
- "I Want U" (2019)
- 2019 Korea Music Video Contest ("Diamond") (2019)
- Taegeon was a former member of M.Crown and Challenger.
- Soohyun was a pre-debut member of LUCENTE under the name Xi.N.
- Sangwoo was a former member of PUREBOY, BLAST, Underdog, and Hi5 (the latter three under the name Kain).
- Doha was a former member of Underdog and Hi5 under the name Baekjin.
- Hawoon was a former member of Challenger and NewTownBoyz.
- Pre-debut member Chibin was a former member of MASC.
"I Want U"