Oshi no Ko opens a new story arc and shifts the focus back to the world of idol entertainment, where the group B Komachi is preparing for their highly anticipated debut. The latest addition to the group, MEM, brings fresh energy and newfound popularity to B Komachi, having previously appeared on the reality show Love Now. However, one point of contention is MEM's age. Although she is 25 years old, she had falsified her age to participate in Love Now, a show primarily featuring teenagers.

In another development, B Komachi is invited to the Japan Idol Festival thanks to their connection with Aqua. This announcement sparks a search within the group to decide who should be their center or main attraction. Both MEM and Ruby are very interested in this position, but they set aside their ambitions when it becomes clear that Kana is also a potential candidate. Despite Kana's hesitation, the group members believe she would be the best fit, leading to some tension within the group.

Kana's attitude toward Aqua, marked by disdain, and her constant self-deprecation raise concerns. Aqua's attempts to reason with her and encourage her to be more polite are met with resistance, which isn't helped by his condescending behavior.

An interesting point in this episode is the group's surprising ignorance of Kana's past music career. When Kana performs one of her old songs during a karaoke session, MEM and Ruby are visibly shocked. This moment suggests that Ruby, despite having been in a band with Kana, knew nothing about her earlier musical activities. Similarly, MEM, despite her online presence and the likelihood of coming across internet articles about a former child star like Kana, seems unaware of Kana's past.

By the end of the episode, the group must confront the challenges of their upcoming debut, the question of who will take the center position, and their dynamic with Kana.