How odd that they essentially rated it like a pornography, if I'm getting it right.
Is Australia normally this strict in rating things? I know here in the US, something like Kill la Kill would air late at night (I think it aired on Adult Swim around 1am EST), and even if it's a bit suggestive, that wouldn't matter much. The FCC allows this kind of stuff after 10PM usually, when younger ones should be in bed.
Australia just seems to be strict in these kinds of things, sometimes too strict.