The game is pretty good, just needs a bit of polish here and there.
The game loop is there, you definitely have a complete game. The art is pretty nice, the chibi girl is really cute looking. Music is pretty good too has a fantasy feel to it.
If squash and stretch could be added through code to the portraits whenever they change from one image to another, that may add a bit of life to them. The magical girl could use a bit more animations and or some kind of procedural ones that add some overlapping animation for things like the cloth and the ponytail, will make it look more dynamic/alive.
Audio and visual feedback could also use a bit of work. When the waves/bullet hits the player and or the enemy, there should be something shown visually or a sound should play to indicate that the reaction. There is already red flashing on the enemies on hit, but maybe it needs a bit more. Things you can consider adding are things like stuttering, particle effects, Hit sounds, screenshake/sprite shake.
Scroll wheel controlled aiming is a bit awkward, might be nicer if the aim is tied to direction of where the cursor is.
Other than that, the game is pretty good, as brought up at the start of the review/feedback.