I like the concept of this game, and I think it has a nice comedic charm to it, especially with the setting of "Heck". Also, I just like bullet hells in general haha. I found it interesting that the two characters seem to be different from one another, since the blue one moves faster.
I do agree with the other comments that the camera should be zoomed out more, since it's really hard to anticipate incoming bullets, or see what I'm aiming at.