They've done it again

This odd advertising site at London Bridge station has been the source for a few of my blips over the past few months. Always off the wall (pardon the pun) and never fully explained. I think there is a comedian out there...or someone with a very warped mind. Any clues what this one's about?  Here are a couple of the more recent ones March 7 and October 11
UPDATE This gives a clue I believe. Something to do with Kate of Gaia. Still odd though