Loona yyxy is the third sub-unit of the South Korean girl group Loona, formed through a pre-debut project titled "Girl of the Month". The unit consisted of 4 members, Yves, Go Won, Chuu and HyeJu. Currently the unit consists in 3 members, without Chuu, who was removed from Loona and consequently the lineup in November 2022. They debuted with their first extended play titled Beauty & the Beat on May 30, 2018. They were the last sub-unit to debut with the pre-debut project, before the group debuted as a whole with their extended play titled [+ +].

Loona is a South Korean girl group formerly under Blockberry Creative. The group was composed of eleven members: Heejin, Hyunjin, Haseul, Vivi, Yeojin, Kim Lip, Jinsoul, Choerry, Yves, Go Won, and HyeJu. Originally a twelve-member group, Chuu was removed from the line-up on November 25, 2022, due to a contract dispute. Starting in October 2016 and lasting for 18 months, each member was introduced to the public through a solo promotional single as part of a pre-debut project. The group debuted as a full ensemble on August 19, 2018, with the extended play (EP) [+ +], supported by the lead single "Favorite" and the title track "Hi High".