A female human is bent over, ready to accept the penis of a male human.
The female human lets the male human know that he can put it "anywhere he wants," meaning she has been given permission to the male human to insert his penis into either the vaginal or anal cavity of the female human.
He then spends the rest of the comic pointing out the atrocities of the proposition.
I mean, I got the joke while reading the comic, but your breakdown was so thorough that I am highly interested in seeing how you can break it down further. Please... Continue.