"Thought you might appreciate the subtlety of this ad, done by a Brazilian ad agency, for a lubricating gel (K-Y equivalent) targeting the French market. They were trying to come up with an ad that is not offensive or tasteless. The picture looks completely innocent until you notice the details... Oh, my God. Look carefully at the details. Apparently, it has created quite a buzz in Europe."
Source
It sometimes takes a little while to understand, but it's a funny advertisement.