It was a great idea to narrate the game. Some parts of it felt like listening to a developer commentary, which I loved. I had two truffles and died and as I was looking for the 3rd on my 2nd life, thinking I knew where the other two were, you chimed in and explained that they have random spawns. The timing was perfect haha.
I was frustrated with W being jump and space being shoot until minute 5 of my failing to beat the boss, when I finally moved my right hand to the space bar instead of the mouse. Problem solved. Old habits die hard, though. I also had slight issue with pointing myself in the right direction when firing, leading me to slam into an enemy or floor teeth from the knock back. I think without considering gamepad support which would be great, using the mouse X vector to change direction for firing, and left click to fire would solve that issue nicely.
Since you said you want to continue developing it, may I suggest adding some sort of feedback for when you or an enemy is hit? I think they may have flashed orange, but with trying to deal with the knock back mid air, I wasn't too focused on if my shot registered. Using a hit/death sound, or something additional visually like screen shake, a small animation, or bullet time right before you're character is hit would feel like a big improvement for "little" effort.
Overall, very funny game! Great job and keep going!