I know, the Aswang is a demon from Filipino folklore that's somewhere between vampire and werewolf. But its name is "ass wang."
I don't have a joke. Do I need one here? Who's afraid of an ass wang? Want to see a good ass-wang penetration? Because there's video of an ass wang probing. Will the ass wang drain your fluids?
I checked with a Filipino friend - the "a" sound is generally pronounced "ah," though the "s" and everything else are pronounced as you;d expect. So if you say it properly, you sound like an English person saying "arse wang." Which is even better.
h/t Edwin Santos