Thanks for playing!
> Is Gabriella the subject of a book Angelica was reading?
Yes, but you had to get past the first boss to find this out since that's when the story truly begins.
I'm not sure exactly what you mean by not being able to aim in the air, but you can't aim upwards while flying, that's only on the ground. And having hits pass through you is on purpose, in these types of games the hitboxes on bullets and the player are smaller than they appear which means you can only be hit if the bullet touches a specific spot on you (When flying, this is shown as the circle with the blue outline on the player character)
Viewing post in Tengoku 1.5: 聖歴史 〜 Tome of Ancestral Vision jam comments
Yeah, I kinda figured the explanation might come up later.
I'm referring to aiming left and right. When flying, Gabriella seems to be stuck facing the direction she was facing when taking off, but only sometimes. Maybe. I'm not sure exactly what's happening, but sometimes she was not facing the direction I was expecting her to.