Koga's going full in on music, to the point where she's kinda blocking out everything else. I've been there (with writing, not music composition), and it feels nice, but you start isolating yourself and when you become conscious of what it is your doing it feels weird and gross. You want to be doing other things, but there's friction and slowness and it would be so much easier if you could just eat and live and breath your obsession.
But you have to live life. You have to take a step back for some time a day, or a week, or a month, or even a year to focus on things that will stop you from just doing that one thing. Oosawa, you have to get them to actually have enough focus on their grades to be in a good position out of school, or else.
Glad to see realistic teen problems portrayed in a teen story though. It's not all romance all the time, sometimes it's just the mundane problems in life.