A Japanese sub-group called QBS was announced in May 2013. The members were Qri, Boram and Soyeon. QBS focused on the Japanese market. They released their first single "Kaze no You ni" on June 26, 2013. It was written and composed by Takanori Fukuta. QBS held a live show at the Sunshine City Fountain Square in Ikebukuro, Tokyo on June 10, 2013. At the show the group performed "Kaze no Yō ni". Boram and Qri also sang their song "Shabontama no Yukue" and Soyeon sang her song "Love Poem".