A very cool concept and well executed.
The walking sfx did become a bit annoying after hearing it constantly xD
I did notice a nice way you made the reflect easy to perform is that the reflected bullets seem to travel towards the mouse. Nicely done.
do miss the shadow theme a bit(besides it being present visually), but you mention this in your GGD.
The game is rather difficult at times, but i think that is part of it's charm. Maybe if got better at it i could have defeated the second boss.
Definitely a nice game, with some polish I could easily see this being released on steam.