:::::It's not valid to say this photo is equivalent to the illustrations in the other sex-related articles; those are line drawings and established artistic images (read: oil paintings one might find in a museum or gallery, for ex.), not photographs.  This photo adds no value but titillation to the article; the mind boggles at the idea that a reader can't imagine for themselves the juxtaposition of a tongue and an anus.  One could possibly argue for the validity of inclusion of an illustration from farther back, thus showing a likely position or positions from which analingus might be achieved, but, again, line drawings suffice.  Question: why are there no naked pictures, much less images of explicit sexual activity, at Jenna Jameson for one example?  You could certainly make a better case for hardcore images being necessary to the understanding of that subject than the case for this picture being necessary to the understanding of this one.  That is a generic tongue and a generic anus and no useful information is presented with the image.