He assured her that there would be sex, just not much of the traditional penetrative kind. His fingers and tongue, he said with a wry smile, were used to compensating for his incompetent penis. ‘And it isn’t totally defunct. It works maybe forty per cent of the time. Okay, maybe more like thirty. If only I’d kept the receipt for the damn thing.’

Tamsin understood that he was making a joke, but she couldn’t laugh at the bitterness in his voice. Instead, she squeezed his hand and said, gently, ‘Doesn’t it depend a bit on who you’re with? I mean, if you feel comfortable…’ Already she was thinking that she would be the one to make the difference.

‘Yes, actually.’ Callum let out a dry chuckle. ‘The more I care about a girl, the less likely it is to work. In fact, you can take it as a definite compliment if my penis hates you.’

Tamsin looked around; there was no one in sight apart from a lone dog-walker, over a hundred yards ahead of them and safely out of earshot. ‘So … can you … masturbate?’ she asked, bringing out the last word with difficulty. Although she had slept with several people, this was the first time she had talked directly about sex with a man.

Callum nodded. ‘That’s never been an issue.’

A duck laughed in the distance.

‘And can I – can I do that to you?’

‘Perhaps. You can try.’ He frowned. ‘Look, it’s the same deal. Sometimes it works. Mostly it doesn’t.’

Then he had explained that his problem didn’t entail infertility. He wanted her to have all the facts so that she could make an informed decision. ‘I’m not asking for any guarantee of commitment or anything like that.’ Callum coughed to clear the formality from his voice. ‘I just didn’t want you to find out and be shocked. And you see, the thing is, my last—’ He stopped. He’d promised himself that he wasn’t going to go into specifics. ‘Some women have been cool with it, but others haven’t. It’s boring for both of us if you have to make excuses later on to spare my feelings. If you’re just not up for it, say now and I’ll understand.’ He sounded almost angry and he couldn’t meet her eyes.

Tamsin was moved by his vulnerability. ‘Oh, Callum, don’t be ridiculous. Of course, of course I don’t mind. Of course it’s not a problem.’

(And anyway: what else could she say?)

They had stopped under a bridge, its damp bricks padded with the bright olive velvet of moss. Callum cupped Tamsin’s face in his hands. It was a long kiss, fuelled by their relief at reaching the end of a difficult discussion.

* * *