Interesting game you made, I can see what you where aiming for (maybe, I could have no clue what I'm talking about.)
Pros: the environment, with the lighting, and the layering it very stunning to look at. the visual effects are also very enjoyable. I love the theme with the Germanic classic of a child lost in the woods of the fey, (but a bit more violent, or less?)
cons: The gameplay doesn't really work well with the Bullet Hell style, the movement can be clunky, making the best strategy just spamming the sword, until everything is dead and you can move on. and the Gun feels unneeded, its slow to shoot, and the bullet travel so slow the fairies will just move a bit out of the way and dodge.
Bugs: Some times I wall jump off the ground? that's strange. Also you can run past all the fairy's killing none, and still get called a murder (That ones just funny.)
Final Thoughts : I did Enjoy the game, from what I played. the best suggestion I can think of if you plan on finishing this entry, maybe focus on the movement and sword play? Give the player some dodge options, like a double jump or dash. make the sword have a small combo chain, with more lag after it. but let the player move while attacking.
or if you want to Keep the Gun make it easy and fast to shoot but weak, and keep the sword as a pure parry tool.
With a bit of work, I think you can make something very fun. Hoped this feedback helped.