Wy has described Australia as acting as a big brother figure towards her. Volume 4 character notes describe him as being courageous regardless of the environment, and that his food is wild because of his wild personality. Australia states during the Christmas 2011 event that he finds the idea of a cold Christmas surprising. In the Halloween 2013 event, Australia is portrayed as a reckless and wild individual who neglects his responsibilities.[3] Character notes describe him as the type to be having a conversation with someone one moment and chasing after a passing cat the next.[4]
In nearly all of his appearances he is depicted with an evil-looking koala. During the segment How Each Nation Watches Movies (located at the end of Hetalia of the Dead in Volume 5), it is shown that Australia gets drunk at the movies. As well, he was pictured with a different koala. The koala appeared to be female as it had eyelashes, blush on its cheeks, and wore a small bow on the right side of its head. The koala was also smiling and in good spirits.[5]