a.k.a you forgot to ask for input to summon a bullet
It's a bug in a debug function. Cool.
What happens if you don't trigger on input, it pretty much summons a bullet every 1/60th of a second. As for the enemies, they have a very small invulnerability time so they don't get destroyed to a button spam. (or in a silly situation like this)
If you wanna get into the loop on what the game is, you can check it out here: https://furria.net/revolve