If the firework is taking place behind her, why is Koakuma commenting as if she was seeing it? And what are they even looking at? The firework's not that way.
pretty sure she turned around, and they're looking at the fireworks we just get to see their expressions and the fireworks instead of having to look at the back of their heads as they watch em or their expressions but no fireworks lol. win/win
It's Gensokyo - Fireworks do not occur in just one portion of the sky, from one single small location with fireworks technicians; Fireworks are a matter of omnidirectional aerial saturation. It does not matter what direction you are looking in, there will be fireworks danmaku where you are looking. Looking at the ground? Ground danmaku fireworks. Close your eyes? Those squiggly lines are now fireworks danmaku. Going down on your girlfriend during the fireworks? Inter-coital fireworks danmaku.
If the firework is taking place behind her, why is Koakuma commenting as if she was seeing it? And what are they even looking at? The firework's not that way.
Because you prefer admiring their back instead of their pretty face, for the sake of seeing the fireworks at the same time? The picture has been built that way only for us to see BOTH their faces and the fireworks at the same time.
Er...... What about it's just that the artist want to draw their expressions too so they were drawn as part of another frame instead of that same frame? You know, over lapping frames.