Wakaba, I'll Do It All! - S2.E16

Star Harmony Academy is holding an open day event for people to come and see the school and how the idols train. Mirai offers to have Wakaba lend a hand as she feels her protege is still lacking something essential for becoming an idol. Wakaba manages to help out fine until an old friend of hers appears at the school, causing Wakaba to become distressed.