Vocalist Yui is a musician from Fukuoka, who originally debuted as a soloist under Sony Music Entertainment Japan in 2005, after auditioning in 2004.
[6] These included keyboardist Mura☆Jun, otherwise known as Jun Murayama, a member of the band Venomstrip and a session musician, as well as Mafumafu, i.e. bassist Katsuhiro Mafune, and drummer Norihide Saji, known in the band as Sacchan.
The band started with recording sessions, followed by a series of secret lives across Japan in March 2013.
The project was officially announced in April 2013, followed by a series of festival performances.
[6] The group released their first single "Tsuki" digitally in June, used in a commercial campaign for cellphone provider au.