The Budokan arc stops being about winning and starts being about what you're willing to lose to get there. Chiyu's vendetta against Yukina isn't just motivation, it's the show admitting that every band's dream costs someone else theirs, and the music only gets better when that tension is real. By the finale, you're not cheering for Poppin'Party because they're the protagonists; you're cheering because the show earned it through four seasons of letting these girls actually fail, doubt, and claw their way back.

Poppin'Party has built momentum as a band, but their biggest test arrives when they learn about the BanG Dream! Girls Band Challenge at the Budokan. This legendary venue represents everything they've worked toward, yet the path there grows treacherous. A formidable new group called RAISE A SUILEN enters the competition with serious advantages: funding, connections, and a leader named Chiyu who carries a personal vendetta. Chiyu is determined to crush both Roselia and Poppin'Party, largely because Roselia's Yukina once turned down her bid to become a producer. As rivals sharpen their craft and push standards higher, Poppin'Party faces mounting pressure, including the challenge of producing their own music video. With limited slots available and the competition fiercer than ever, every practice session matters, and the band's friendship is put to its hardest test yet.