loiterer

One who loiters, one who lingers or hangs around.

Though unusual in the Dublin area he knew that it was not by any means unknown for desperadoes who had next to nothing to live on to be abroad waylaying and generally terrorising peaceable pedestrians by placing a pistol at their head in some secluded spot outside the city proper, famished loiterers of the Thames embankment category they might be hanging about there or simply marauders ready to decamp with whatever boodle they could in one fell swoop at a moment's notice, your money or your life, leaving you there to point a moral, gagged and garrotted.