MAMAMOO is a four-member girl group formed by RBW in 2014. The members are Solar, Moonbyul, Wheein, and Hwasa. The group officially debuted with their first EP HELLO and its lead single "Mr. Ambiguous" on June 19, 2014. Their debut was considered by some critics as one of the best K-Pop debuts of 2014. On November 21, MAMAMOO released their second EP Piano Man with the title track of the same name. On April 2, 2015, MAMAMOO released "Ahh Oop!," the first single of their third EP titled PINK FUNKY. On June 19, MAMAMOO released their third EP PINK FUNKY and lead single "Um Oh Ah Yeh," which peaked at number three on the Gaon Chart, becoming their first top three single. The group’s fifth EP PURPLE, released on June 22, 2017, placed first in Billboard's World Album Charts. On March 14, 2019, MAMAMOO released their ninth EP WHITE WIND with its lead single "Gogobebe."