Covered in the article (I realise, of course, that it is most improper to read those on this website). Stylised drawing of two humans with the naughty bits obscured based on how the picture was framed. However, that seems to have only been one account in any case and is probably not the thing to focus on.

i'm aware of the picture. i was trying to bring focus to the fact that no one has an intuitive definition of "non-explicit nudity" because these policies are kept intentionally vague so that anyone can be in violation at any time for any reason and the selectiveness with which they're enforced means that they can always be used to accomplish authoritarian goals with a fig leaf of non-authoritarian reasons for banning people.