So the next Saturday morning, not a minute after Kathryn had left to catch her bus, I was upstairs. I stood in front of her underwear drawer for a few minutes, listening to my own breath and knowing I was going to look inside the sweetie tin.

I delved my hands into her piles of knickers. My fingers trawled through cotton and elastic until I felt the hardness of the tin. I dragged it out. A pair of pink knickers that I hadn’t seen before came with it and I flicked them back into the drawer.

I sat on the bed, opened the lid and slipped off the garter. My fingers were trembling, the tips wet with sweat. I was sure I’d mark the garter, sully its whiteness.

I fanned the photos out in my lap.

As I picked up each one and examined it, the thing that struck me was that you could tell there was no one else in Jack and Kathryn’s lives, because no one was ever around to snap them. There was only one photo of the two of them together. In all the others they were alone, but in the same location; there’d be one of Jack standing there, posing, and then another of Kathryn in exactly the same pose, in exactly the same place. Like they were mirrors of one another. As if they couldn’t bear to do anything differently.

Kathryn on Jack’s motorbike, her bare legs against the metal, her black eyes squinting against the sun. Kathryn on a picnic blanket, her thick hair curled up on the top of her head, holding what looked like a chocolate éclair to her open mouth. Laughing.

It seemed that in all the photos her mouth was wide open, her lips pulled back over her teeth. I didn’t remember ever really looking at her teeth before, but now here they were, bared. And her chest was pushed out into the air; each breast seemed to be showing itself somehow, showing itself to him.

A couple of the photos were on a beach. I guessed from the new-looking pier that it was Bournemouth. One of them showed a flat expanse of sand, with KATH LOVES JACK scraped into it. It was the capitals I hated. So definite. The sun must have been low behind him when he took it, because I could see his long shadow in the corner, spreading over her letters.

There was only one photograph of the two of them together, in front of one of the pools by the power station. They must have stopped some stranger and asked for a snap, Jack smiling, handing over the camera, explaining how it worked, no doubt, while Kathryn stood waiting and laughing in front of the pool, one hand on her skirt to stop it blowing up too much in the breeze.

In this photo Jack was leaning forward, grinning, and Kathryn looked so small beside him you might have thought she was his little sister. She had both arms flung around his middle, gripping him, and her head was squeezed into his armpit. Behind them, the pool looked black, wide and bottomless. I studied Jack, his confident pose, the way his hair stood up off his forehead, the way his clothes seemed just that little bit too large for him. He looked like he had room. His big body had room for manoeuvre.