(Aa ieba kou iu; “If (I) say this, (you) say that.”)
Quibbling and back-talk. Arguing for the sake of arguing. No matter what advice or instruction one person gives, the other objects to as much of it as they can, often through insincere and annoying rhetorical strategies such as hair-splitting or ignoring the main point in favor of trivialities.
This idiom has only one verb (used twice) and two adverbs, although their grammatical status is a little obscured by being quoted speech. We begin with ああ (aa), “in that way.” This is followed by 言う (iu), “to say,” in hypothetical form. Next comes こう (kou), “in this way,” and then again 言う in a form that could be sentence-final or prenominal.
People unfamiliar with Japanese should note that there’s a pattern – the ko-so-a-do set – that informs a number of groups of words. The ko element is roughly equivalent to “this” in English, for something relatively close or related to the speaker. So and a are different flavors of “that”: the first is relatively close to the listener, while the latter is relatively detached from both speaker and listener. And do is the interrogative form. So for example, koko is “here,” soko is “over there (by you),” asoko is “over yonder,” and doko is “where?” (Yes, there are nuances and weird fringe cases, but that’s the gist.) The kou and aa of this phrase, along with sou and dou, are another such set, although aa is not in especially common usage in modern Japanese.
A number of variations on the theme of this idiom use other oppositional pairs such as east and west, left and right, or even mountain and river! Some versions may add the speech-marker particle と (to) or elide the second verb entirely.
(“Kekkyoku, saakuru wa sesshi gatakute, aa ieba kou iu renchuu ni nottorarechatta kara, yameru shika nai to omotta.”)
[“In the end the club was overrun by a bunch of bothersome types who always had to contradict everything you say, so I thought I had no choice but to quit.”]