^^^^ No one skinned the lion. Or at least not the lion from the previous page. The lion girl is an aquilifer, which is a rank in the ancient Roman army. Aquilifer carried the eagle standard of the legion into battle and thus had immense importance. Lion fur, with the lion's head covering the helmet, was part of their uniform.
This was actually standard practice in the Roman army, lower ranked standard bearers who carried the standards of smaller units within a legion were also clad in fur, wolf and bear fur depending on the rank, lions being reserved for the aquilifer.
If you are wondering where from did the Romans get all these lion furs, lions were actually present in Europe in Antiquity, mostly in the Balkan peninsula. They went extinct by the 3rd or 4th century AD, in large part because of excessive hunting for sport and for the Roman entertainment industry.