>>2330519Actually, it's even more complicated than that:
Erika was grateful to Miho for saving her, but unhappy about losing the finals.
Then Miho decides to give up due to being treated like a pariah, and transfer away without warning. Erika felt betrayed.
And then, out of the blue, she learns that Miho is now the captain of another Sensha-do team (she has no idea Miho was roped and manoeuvered into it by Anzu). She feels doubly betrayed and goes into turbo-bitch mode.