From Russian perspective it doesn't matter because they value Korean life the same: zero. Koreans are expensive, though. God knows what putin is trading for their troops. Probably rocket and nuclear technologies.
From military perspective Koreans are useless cannon fodder for to the language barrier and unaware of modern combat full with FPV drones.
I'm not sure of the accuracy of this, so take it with a grain of salt, but I did hear that rocket and nuclear technology is indeed part of the deal - terrifying. NK will also provide artillery shells.
> From military perspective Koreans are useless cannon fodder
Well, that's the soviet doctrine. Men are useless cannon fodder. It does give the NK the chance to catch up on modern combat.
From military perspective Koreans are useless cannon fodder for to the language barrier and unaware of modern combat full with FPV drones.