Moonbyul

Moonbyul (문별), born Moon Byul-yi on December 22, 1992, in Bucheon, South Korea, is a rapper, singer, and songwriter who became one of K-pop's most distinctive voices on gender expression and artistic individuality. As MAMAMOO's main rapper, her sharp lyricism, confident swagger, and androgynous stage presence challenged the genre's conventional femininity from the moment of her debut under RBW Entertainment on June 18, 2014.

She originally auditioned as a vocalist but switched to rap six months before debut -- a pivot she executed so completely that she became the group's creative anchor. She is also a member of the Mamamoo+ sub-unit. According to the Korea Music Copyright Association, she holds songwriting credits on over 100 songs, having co-written her own rap verses from the group's earliest releases onward.

Her solo discography spans nearly a decade: debut single "Selfish" (2018), mini-album "Dark Side of the Moon" (2019), studio album "Starlit of Muse" (February 2024), and third solo EP "6quence" (2025). She marked her Japan solo debut with the single "Aurora" in February 2025. In March 2026, she announced forthcoming single "REV," set for release March 25, 2026. Her fanbase, Byulddongies, and her rap alias Moonstar -- a direct English translation of her Korean name -- recur throughout her lyrics as a personal signature.