Cute little shooter. Love the color palettes, the enemy designs, the parallax backgrounds. Very atmospheric overall. Sound effects are good, too. And there are some very original touches--the angled shots, the heat/cooling mechanic.
I found that the character moved too fast for me to control comfortably. And I generally didn't have time to destroy many enemies, since they require multiple hits; rather, I found myself dodging them if I wanted to survive. I think the speed of the player character may need some balancing, especially since you progress horizontally (i.e., you are strafing along the vertical, narrower axis).