All this lavatorial stuff, and H's post from the past, reminds me of a similar incident I recall witnessing back in the dark days when I was at nautical college and staying in the halls of residence.
A number of us callow youths decided we'd have a boozy weekend away from Plymouth, staying in a beach hut near to Fort Bovisand dive centre (with bar etc.)
Having drank rough cider all the way there on the bus, then drank various fluids in the beach hut, we decided to make the short(ish) walk to the fort along the coastal path to have a few more bevvies that evening.
This is where my memory gets a bit murky, but I recall one of our breathren had his birthday that weekend, so we comprehensively Mickey Finned him.
Later, he could not be found, so we drunkenly searched the fort for him, only to find him asleep on the floor of the shitehouse, naked and covered in his own excrement and vomit.
It transpired that, whilst sat having a dump, he felt the need to chunder and slid off the seat and rolled around to barf down the pan. In doing so, he layed a turd on the toilet seat, which he then put his arm on, and most of his upper torso - it was not a pleasant sight.
He then chundered over himself and continued to shat on the floor - suffice to say that we refused to allow him back in the beach hut that evening.
Oh happy days