The second generation idol. Compared with the first generation idols, Sora and Haena's planning abilities are more systematic and meticulous. Different from the past, they are "K-pop idols" who make music with overseas markets in mind from the beginning. This is different from the first generation, which is often called "second generation idols" in Korea, so Sora and Hina is called the second generation idol in Korea. Idol refers to the object that is worshiped by people. It is analyzed by genus plus species difference. Idol is the species, the object is the genus, and being imitated by people is the species difference.