[you know him well enough to know that the answer is yes, that he'd like to tear them apart himself, in vengeance for what was done to his parents, for making him lose what mattered to him most, and though she doesn't know it and because he's never told her what was done to him, he blames them for what's wrong, because if there were no beastmen, there'd be no other part of himself that enjoys bloodshed. but yeah, that's not the sort of thing Nebula would admit to, so he shakes his head]
I think it'd be good enough just to not have to worry about them anymore.