In the books he had read, both in medieval poems and in novels set in run-down passages of Paris, the lovers were obsessed yet pure. If there was physical lovemaking between them it must have taken place on some higher plane, where such things were allowed. A part of him aspired to this kind of life, but the trouble was that it seemed entirely literary: he had seen no examples of it in his home town – in the husbands and wives, whose marriages seemed like a business partnership, or among young people, whose schools had kept the sexes apart. At the opposite extreme, the street girls of Vienna seemed to be offering the kind of coupling he had glimpsed only once, when his father had taken him to see a supplier at a pig farm. Some natural arrangement, he felt, was being made elusive by a society that had found no way of accommodating it; and it was puzzling that the capital of the greatest empire in the world should have come up so short on the simplest principle of life – like a horse that had thrown its rider at the first fence and whose subsequent run was therefore of little interest.

Friedrich warned him off the line girls with stories of syphilis and the treatments that followed. ‘They coat your body in mercury and all your teeth fall out. Bits of your nose drop off.’

‘My nose? I wouldn’t mind that.’

‘And in old age you go mad. You imagine you’re the king of Spain.’

The combination of ignorance and fear had crushed Anton’s instincts, but in his second year at the university he had spent three months in Berlin and, on the night he was due to leave, managed a fumbling connection with his landlady’s daughter. He was quite sure there was no chance of disease because Gudrun was a good girl, as her mother often said, though for some months he dreaded a letter informing him that he was the father of a little German. After his return to Vienna he decided that, having at last joined the ranks of authentic men and – unlike everyone else he had ever heard of – without recourse to a prostitute, he would not be bothered by such things again.

Yet at the age of twenty-six, there was still that lung-stabbing ache that could be brought on by a single glance; and there was still Delphine at Erich’s house. In the days after their first meeting, her face seemed to be all he could see. He focused his thoughts on the thin line of hair on her upper lip in the hope that it might put him off; but it seemed to have the opposite effect. He wanted to run his tongue along it. He was fascinated by the fact that she was older, with all the experience that implied – Paris, music and late nights in the Latin Quarter. ‘One of us is married, the others wait for husbands. Or so my father thinks.’ How playful had that remark been? At night he fell asleep to the sound of her chord changes.