Everything about those who sleep on pavements - everything about them should remain a half-truth. A half-mystery. If you find it in any way romantic, do not ruin your good story by altering the ending. Walk past, don't say a word. One syllable casually dropped - and there would be no end to bad teeth and petty revelations. The whole city could be obliterated for all eternity. Or even - and this is much, much worse - for you.