It's just too difficult in my opinion. The first thing you see is a screen full of bullets, and an enemy which would be hard already without the player's projectiles disappearing if you try to fight it at a - for me - reasonable distance. Also they have a lot of health. At my best try I managed to defeat one... So it feels rather unfair...
Overall, from the description, the mechanic, that you can have the enemies, who you have killed, fight on your side sounds interesting and fun, and it really is a bullet hell. But sadly it was way too difficult for me.