The Association and School Idol Club's joint training camp is over, and each temporary unit now hones its performance skills in anticipation of the school auditions. Meanwhile, Shioriko feels suffocated with Kaoruko back home.

Life with Kaoruko back at home has thrown Shioriko for a loop, while laid-back Kaoruko has begun working as a trainee teacher. What kind of lesson does Kaoruko have in store for her students?

Student council secretaries Satsuki and Uzuki draft up a perfect plan for school idol Shioriko, who puts her all into practicing to make it a reality. But the appearance of a certain duo dampens her enthusiasm.

Kaoruko crashes the School Idol Association's practice and joins in with Lanzhu to give nonstop advice to Shioriko, which sends her running to the Club. There she sees Kanata and Haruka, a very close pair of sisters.

After escaping to the Club, Shioriko sees how close Kanata and her younger sister Haruka are. She and Kaoruko are so different that it confuses her. To cheer her up, everyone with a sister meets up at a diner on their day off.

At the diner, Shioriko hears about warm sisterly bonds and learns that relationships between sisters come in all shapes and sizes. She is invited to Kanata's house, where she meets her sister Haruka and has a delicious dinner.

At a sleepover at Kanata's house, Shioriko sees Kanata and Haruka's sisterly love up close. She realizes that she has a way to communicate the feelings she'd given up expressing to Kaoruko. She heads home ready to speak her heart.

Shioriko is tired of Kaoruko not listening to her and wants to do a live show to tell Kaoruko how she feels. When she comes to you for advice, you suggest getting the Association involved and start coming up with her song.

An intense song that expresses all of Shioriko's bottled-up feelings is finally complete. Next up is discussing choreography, stage effects, and other details for the live show. But Lanzhu's ideas are all too out there.

It's finally the day of Shioriko's live show and Kaoruko is brought to the auditorium. Up on stage, Shioriko starts telling stories about her big sister and their colorful past together!

After years of bottling up her feelings, Shioriko has left what she could never express to her sister out on the stage. What does Kaoruko feel after the show?