She is a tough on for sure, and it's unlikly you can beat her when she is first available. If anything, head back to 14F and grind for about 3-5 levels, then try again. What level is your Reimu?
Reimu's at 59. I know I'm slightly underleveled for the fight, but after figuring out how to keep her from spamming
I can see it's still a very doable fight.
I got her to use
on my last two attempts, but the first time my party got nuked when
had an empty active gauge, and the boss's auto-regen got about five turns, so Master Spark didn't take her out like it should've. I could've actually won that time if I had switched Patchy in after that instead of expecting to be able to have my living wall survive another turn.
That said, after fooling around with my team I've discovered Chen is amazing for this fight.
EDIT: Okay, I keep losing after she uses
now. I can get off a Master Spark, but anyone else I can switch in either doesn't move soon enough or hit hard enough before getting blown up.
EDIT2: Between paralysis, speed debuffs, and the retarded speed this boss spams at,
this went on for about 10 minutes (14F related). I couldn't stop laughing.
EDIT3: Patching to v2.06 for the fight now.
significant buff should help unbelievably.