Australia has begun cracking down on the importation of adult goods from Japan, mainly their comics. This is due to how certain taboo topics containing family members and children are often involved.
Even the possession of such anime images containing children could warrant an arrest, such as in the case of a 52 year old man from southern Australia who was given a suspended jail sentence back in 2015. There are also numerous other cases that can be found online even involving years of jail sentences.
"Lolis" are also completely illegal in Australia and have been since quite a long time. There is a zero tolerance policy in place which also covers the gray areas. Things such as flat chested women or just too young looking adults.