Destroyermen/YMMV

Complete Monster: The Grik. All of them.
- That racist asshole who raped a 'Cat in book two. Walker's NCOs justifiably lynch him for it.
- Captain Kurokawa. When the Grik tell him he has to pay a penalty for a defeat, he selects some of his crew he considers least useful and turns them over to the Grik to be butchered and eaten, telling himself they deserve it because they "failed him." What makes him more dangerous is that although he's evil and insane, his accomplishment in persuading the Grik to alter some of their ancient customs shows that he's (at least in some respects) brilliant.
High Octane Nightmare Fuel: At the climax of book one, Matt and his crew team up with the Lemurians to board a Grik ship. The battle is horrific enough (though not without several badass exploits from humans and Lemurians alike), but then everyone goes belowdecks, to find a "brig" where Lemurian captives are being butchered alive for food, and the survivors are Forced to Watch. Oh, and this comes immediately after a human skull is discovered on the ship. That the Grik were keeping as a trophy.
Magnificent Bastard: Again, Silva. He has a habit of dealing out a ridiculously appropriate (and often over the top) lesson and/or punishment to anyone he thinks needs one. For example: one sailor is mocking the coxswain who has become terrified of the sea since arriving in the new world (for very good reason, and the coxswain continues to do his job despite being humiliated by his own fear). Silva's response? To pull the pin on the chain the mocking sailor was leaning against, leaving him to go tumbling over the side and only save himself by grabbing the chain. Afterward, he's afraid of the water.
- Let's not forget his "prank" on Chack (a Lemurian who joins the Americans on Walker): Silva proclaims Chack's sister to be his wife...and she goes along with it! Poor Chack was this close to murdering Silva when that happened.
Either a shout-out or a bizarre coincidence is that the New British bishop who officiates at Captain Reddy's wedding is named Akin Todd, which seems like a reference to U.S. Congressman Todd Akin. But why would anyone want to shout-out Representative Akin, infamous for his idiotic claim that a victim of "legitimate rape" usually won't get pregnant? Bishop Todd is said to be rather displeased with the introduction of Lemurian notions on feminine equality, but doesn't seem quite as reactionary as the politician.