When me and the missus were in Battambang for 5 nights last month we witnessed this slightly worrying sight.
We were wandering around the centre of town and close to the main market area.
Into sight came this local looking bloke with shoulder length straight hair.
He was wearing a t-shirt and flip-flops, but nothing else.
I watched him for a minute or so. He was in a world of his own, and judging by some of his actions he had definite mental problems.
It was very busy around the market at the time, but the poor bloke was almost completely ignored by all the locals.
We then moved on.
Later that afternoon we were enjoying the 'Happy Hour' in Flirt Bar and talking to the English bloke who runs the place. I mentioned what we 'd seen earlier in the day, and he said that the bloke has been around for a long time, and there also used to be a woman regularly 'on parade'!
I'm surprised people like this aren't on the radar of an NGO or two, and are definitely a bit of an embarrassment for tourism.