Sosuke Yaotome, who is trying to pull out the rising popularity of Tamaki and Sogo, has taken advantage of the weaknesses of Tamaki who hastened his debut and invited them. After learning about the circumstances of Tamaki, Riku and his friends talk directly to President Kotori Yu so that he can make his debut as IDOLiSH7. However, the president's decision is to make a debut with only Tamaki and Sogo, who were targeted by Yaotome, based on the possibility that all seven of them will make their debut in the future. At that time, IDOLiSH7 receives a request to appear in the music program "Music Festa".