loona (written as looπδ, ; ) is a south korean girl group formed by blockberry creative. the group was first shown to the public through a project which began in october 2016, where each of the twelve members were revealed one after another by releasing a single over the next eighteen months. the members have formed three sub-units: loona 1/3, loona odd eye circle and loona yyxy. they started as a full group with the extended play, "[+ +]" (2018), supported by the lead single "favorite" and the title track "hi high."