Further goes quite a detailed description of a character appearing in Peter May's The Man with no Face, where the italicized sentence is not quite clear to me.
The door opened and a lean man in a baggy brown suit stepped briskly into the office carrying a slim, beige folder. The crown of his head was bald and shiny, but dark, wiry hair grew in bushy abundance round it, and he wore round-rimmed tortoiseshell spectacles over a long, thin nose with flaring nostrils. He would be in his fifties, Bannerman guessed, with a grey, deeply creased face from which peered two small, very dark eyes behind the spectacles. His suit was well worn and fitted only where it touched. His waistcoat was open, a thin brown tie hanging from an open-necked white shirt. He carried about him an air of age and defeat, like a schoolmaster nearing the end of his career, reeking of chalk dust and blackboards and thankless years.
The question is, what small detail might it add to the man's outfit having the signs of extensive use/wear? How could the phrase "and fitted only where it touched" be paraphrased?