Happy Hump Day

I regularly saw "Happy Hump Day" pass on twitter and never knew what it meant. I also didn't notice that it was on a wednesday, did not pay any attention. Till recently and decided to google for information: This is basically what it means:

But for the connoisseurs (which I am not) guess it also has an erotic touch, cuz the following pics is what you get when search for "happy humpday meaning". Wondering if they only use this in the USA.

Shake everything you've got