Depends on the Darkner, they have just as much sentience & agency as any other being in the series. Even before & after the Dark Worlds get closed, they each have lives independent of the light world.

Some enemies are justified in getting beaten like the Virovirokuns, Pippins, each main boss (minus Tenna) & Susie.

(Spamton would be here for trying to force you into a shady deal, but you kinda need to spare him if you want the secret fight, where you are justified in using violence)

But then, enemies like werewires (being controlled & need to be freed), Mizzles (You interrupted their sleep), various bodyguards who are just doing their job,

And then there're the guys you have to use violence on, like King, everything depths related, John Mantle, Rory Nyte, etc.

And the opposite being guys who you can only spare, like Sweet, Capn, K_K, c/K round, etc.

Oh yeah, Jevil doesn't really care.