I wasn’t ready for him to go. I couldn’t bear it. We’d only just come back to each other. The panic rose up and I wished I could go to the little room now and talk to him.

‘You’re here!’

I jumped as someone sat next to me.

It wasn’t Troy.

I turned to look, not quite wanting to believe it, but it was. It was Joe.

‘What are you …’

‘What are you?’ he said.

He had bunked off school to come here early and found me doing the same thing. We’d turned up in the same place at the same time by chance.

‘Amazing!’ I said. A woman walking past flashed me a glance, and I took my phone out and stuck an earphone in so I could talk without drawing attention. ‘I’m so glad you did this. Joe, I heard from Troy. He’ll be here at four. He’s come over. We’re going to find out what happened.’

We stared at each other. We had an hour to say everything we would ever need to say, and the pressure was too much. People walked by in both our worlds. We talked about Venus and the people around us and time and space, but I could feel the universe pulling us apart. Every second that passed took me away from him, as I grew up and he didn’t. It was a succession of tiny moments that already added up to something huge.

He would always be my best friend. If he stayed, though, we’d stop being contemporaries and, although I’d always love him, I’d become his older sister, his aunt, his mum, his grandmother, while he stayed the same. Raffy would catch up and overtake him in no time at all.

I wanted to say all that, but there was no point. We already knew it.

‘Lara wants to stay,’ he said. ‘I asked if she wanted you to try to work out what happened to her, but she said no. She’ll take her train journey every day because it might be the best it ever gets. A while ago I would have thought she was mad, but I see it now. I do see it. Where’s Leo? What if he’s nowhere?’

We looked at each other. I could sense the shift in him. He’d been scared of living this day again and again and again for the rest of time. Now he was scared of not doing it.

When Joe stood up, I realized what he had to do.

‘What are you getting today?’ I said.

He shrugged. ‘A cup of sick would be good. Probably a Coke.’

‘Get me one?’

He smiled. ‘I’ll try.’