Groomer?
It may have been a performance area, and they enjoyed ribald comedy performances.
Let’s be fair about this. If I had a couple of leopards on either side of me I might well feel an urge to pee too.
it’s possible that the three-foot-tall relief served an educational, rather than purely aesthetic, purpose...
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Well, it is kind of obvious. The thing is saying, “kid! careful! get caught touching your peepee in public and you get fed to the animals!”