Two years after training, I was back from Chechnya. She invited me to Christmas with her family. She had always depicted her own life as a home counties nightmare of perfection: Cheltenham Ladies College, parents trying to marry her to stockbrokers, doctors, clergy. I mean, fucking clergy …

They didn’t seem too nightmarish to me. After lunch she showed me how to pick the locked drawers in her father’s study, which contained photographs of his lovers, some teenage, some sadomasochistic.

‘So which locks do I pick for you?’ she asked. ‘You don’t talk about your background. Is that some stupid Six thing? I don’t know how you got here. You were in Cambridge, you were playing soldiers on the side, got a tap on the shoulder … ’

Boxing Day, we borrowed her father’s Aston Martin and drove to where I grew up, a former local authority house in Croxley Green on the edge of London, empty since my mother’s death two years earlier. I kept up with bills, never slept there, let the maintenance go. I hadn’t been back in a while. Joanna wandered the place, picking up vodka bottles, blister packs. There were few traces of my mother’s succession of boyfriends, who evaporated once the pillow needed to be pressed. Most of the bulbs had gone and the winter light was hard.

‘Your father?’

‘Left when I was four. I don’t really remember him.’

‘Of course. I should have guessed.’

She lifted an unopened pack of oral syringes and gave me a quizzical look. I filled one with vodka.

‘Open your mouth.’

I described my mother’s late embrace of alcoholism, and the six months spent feeding her vodka and orange as her body closed down, a scene that wasn’t without its own raw beauty. It brought me a cool, enveloping nihilism that later became entwined with what others perceived as courage and determination. I could survive anything after that.

I found a candle, lit it.

‘What are you thinking?’ Joanna asked.

‘It feels like Christmas.’

It took me a long while, taking out the memory of those two days and handling it, before I realised why she had invited me to her parents’ place. She wasn’t using me to deflect attention. She liked me. She picked through books in my old room – German medieval poetry, critiques of Thomas Mann – found some old photographs.

‘P Coy?’

‘Pegasus Company. Training for the Parachute Regiment. Playing soldiers, as you said.’

‘You look like you’ve been boxing.’

‘They call it milling. It’s part of the selection process.’

‘What do you do?’

‘Punch your opponent in the face as hard and as frequently as you can. One minute, no pausing, no trying to defend yourself.’

‘Why?’