At Uzume Lesson Studio, Maiko reveals to Tsubasa and Eleonora that they are going to become an idol duo, with Barry in charge of training them to better be in sync. Ordering Itsuki to go with them, he has them head for the Idolasphere.
At Illusory Daitou TV, Barry has Tsubasa and Eleonora perform Session Attacks to help them read each other's movements, keeping track of their progress with Tiki's help (though this isn't revealed until after the training). Eventually, Tsubasa and Eleonora are able to match each other's movements, much to Itsuki and Barry's delight. They release their first single as an idol duo, Dream Catcher, though Eleonora still has doubts about Barry's qualities.
Completing this side story unlocks Barry's Backup Skill One More Mastery, which increases the mastery of Carnage gained through battle, and Tsubasa and Eleonora's Duo Art Dream Catcher, based on the song performed in this chapter.