Responses
I think they are supposed to be the bickering couple type. Kabu has to act like that so he can set Onoe off, cause some arguments (playful or serious), and then later they make up. If he didn't act that way they wouldn't argue much. Look how Onoe is with Masa. He's pretty cheerful. He only gets all riled up and angry with Kabu.
I suppose that is one way of looking at it.
The problem is he's a condescending jerk to EVERYONE.
Personally, as I read this story, I've become more and more convinced Kaburagi is simply not a nice person.
Whether he's right or wrong, Kaburagi always seems to go out of his way to be condescending and really disrespectful.