Hiya, I'm so glad you liked it! Hopefully Auggie's route will be done soon...! ^_T
The audio files should be easily accessible! If you want to save one, just remember to copy+paste instead of dragging it out, or else you'll get an error when the game can't find the file anymore :D
Open the Iris folder > game > audio > (music files)
The one you're thinking of might be called "Final Battle" or "Awakening" (to be renamed in the update).
Well that was easy, thank you!! Yeah, turns out I meant Awakening. Maybe it's just a Pavlovian response because so many of the scenes where this song plays really moved me, but I love it nonetheless!
I actually wanted to link other people to it (there was a discussion on Reddit about favorite songs from otome games and this was my first thought) but I notice there's no artist information on the file, I don't suppose you could tell me who made it?
Glad you got it! That song will be the theme of February (and like I mentioned, renamed aptly later lol).
The composer's name is Cryset! https://twitter.com/crysetbase
