Good story, but I still don't understand the technological level of this world. Like from where MC knows about guns? Isekai? Or it already exists in this world? There was no mention of this in story so far. It would also be nice to have a better understanding of the world in general.

I still don't understand, does firearms already exist in this world, or did he gain knowledge elsewhere?

Author rn (I was afraid that this would be another story about an interdimensional cafe):