@Bunnymoon105 I can't help but think that this is because the MC is the only one who can stand up to him, since no one else dares to do so not even the Hounds, who are known to be his right-hand people. Perhaps the ML sees him as someone who isn't afraid, whereas he views everyone else as mere dogs. A dog obeys and doesn’t challenge its master, but the MC doesn’t quite do that he even manages to change his mind....
I could be wrong about this; after all, the ML is a mystery himself, even more so than the pretty MC.