"Wait for us! Hi, everyone we're SATURDAY!" Saturday consists of seven members. On July 7, the first member of the group, Yuki was revealed, followed by Ayeon on July 8, Chohee on July 9 and Haneul, Chaewon, Sunha, Sion on July 10.
On July 10, the first teaser of their debut single "Mook Jji Bba" was released.
On July 16, the second teaser of the single was uploaded.
They made their debut on July 18.