The culture clash in His Majesty's Dragon is so funny and interesting. Laurence realizes that Granby hates him not just because of the whole "Navy interloper" thing (which he found understandable and even forgivable) but also because he's holding a grudge on Dayes' behalf (which he does NOT find forgivable, due to how much Dayes upset Temeraire). Granby's keeping himself just barely on the "passive" side of passive-aggressive and Laurence decides something needs to be done, but he's so painfully Navy that he's like, "It has become necessary by his actions to make it clear I won't tolerate his disrespect. He'll know that his distaste for me is returned, but he won't keep pushing it if he knows I'll hold him accountable for the insubordination."
Like, all of that is what he's attempting to silently say when he insists Granby call him "sir", and in the Navy it would've been understood implicitly. It does not at any point occur to him that Granby wouldn't hear that!
But what Granby hears is, "I think that the Navy is better than the Corps and that I specifically am better than you specifically. Every conclusion you've jumped to about me is right. I will be taking advantage of my dragon's great value to the Corps to get my way."
And then he spends the next month calling Laurence "sir" in the sassiest, most pointed way he can muster, because his response to that is "You may outrank me and due to your ability to destroy my career I will obey your uptight demand, but I will not mean it. My respect is something you have to earn, and you have done nothing at all to do that."
And what Laurence hears is "I am the sort of person who will reluctantly keep to the letter of the rules of civility but not to the spirit. I am so dead set against the very premise your presence here that I am going to remind you of it every time we interact."
Chef's kiss. Can't believe they're gonna be lifelong besties and neither can they