The gameplay was a fairly standard horizontal shmup. It didn't feel like it was worth it to try and use the flamethrower as most of Kaguya's patterns kept you out of range. A hitbox indicator would have been useful though it wasn't hard to figure out the hitbox was Mokou's chest because aimed bullets would go towards it.
The visuals were cute, probably my favorite part of the game.
The sound was all taken from Len'en games, which I'm not sure is allowed. I read JynX's guidelines and it seemed to discourage it, though you could interpret the guidelines as allowing it because they mostly specified not using data from the official games in paid fanworks.
The game was entirely a shmup, so there wasn't much in the way of story or writing to review.
The jam theme doesn't really make an appearance beyond Mokou having infinite lives and the game featuring Mokou and Kaguya.