Oh sure, Setsuna might be more willing to forgive Mir than Mir herself-but I mean, come on, what are the odds that she'll be able to arm herself with an argument that Mir will actually listen to?

...just go to the Silver Horn and get EXEC_Harmonious, and we can skip ahead a whole year. You may need Siren/Ellen to sing it though.

Good to know! Mir is the very definition of a glass cannon, so one good hit should knock her down in most fights when she's corporeal. If she doesn't have a body though...ugh, getting her to stop is really hard. She just makes monster after monster.