Great style!
I love it when a game manages to avoid most cliches in visual design. This game did that very well! The look, feel, and sound had me from the very beginning, and they stayed enthralling until I died.
The gameplay was very fun, but my gun felt pretty useless after the very first section. When none of the enemies are killable, it's an avoidance game, but it looked so much like I should be able to shoot things, that I never stopped trying. The bosses always were a relief in that way; it felt good when the bullet hit something and actually had an effect.
Lack of a continue option is the only thing keeping me from playing this longer. I got to the boss like a spiky-snake thingy, and died. While this game is definitely fun enough that I want to keep playing, replaying the first few sections sounds horribly boring right now, after I'd already made it that far. The game can still be hard without making the player redo the entire thing if they screw up one too many times. If you had fewer lives, but with checkpoints after each boss, then the game would be excellent.