The main character in this game enters a pact with a dragon which allows them to communicate with each other and the MC to take control of the dragon. The MC is depicted as bloodthirsty simply out for killing while the dragon as a being standing above everyone else, mocking humans especially for being a petty species.
Pretty early on in the game, when riding the dragon, you have to shoot down enemies out of the sky. After killing a certain amount, the dragon goes:
もうやめておけ!やつらも生き物だ、死して横たわる権利はあろう。
I'm not really sure what he's trying to say here. The dragon himself seems to switch between a "let them live" and "everyone must die" mentality pretty often throughout the game and it's kinda hard to pinpoint what exactly he wants from you at times. I assume here he's mad at the MC for mindlessly killing enemies but I'm not really sure what exactly he's trying to get at here.
If 死して横たわる means "to lie dead" (which I guess it does), how does 権利 come into play here? They have a right to lie dead? Doesn't make much sense to me.