I often thought about taking a day off to have a break from them. But it was GCSE year, and I was only going to be at this school for a couple more months, so I forced myself to keep coming in.

Mr Morrow was at the other end of the corridor, so I pulled my stupid blazer on. Being caught without your blazer in the corridors, or with your skirt hitched up, or (most criminal of all) wearing the demonic ‘branded trainers’ was the outside world’s equivalent of being caught with a bag of cocaine and cash, speeding the wrong way down the motorway in a stolen car.

‘All right, Ariel?’ he said as we passed, but thankfully he didn’t stop.

‘Fine, thanks,’ I said. Izzy had disappeared to hockey. I stuck in my earphones and set off home.

I would once have been doing hockey too, but I stopped everything like that when Mum got ill because why would you chase a stupid ball round a pitch with a stick when your mum might be going to die? Then she did die, and of course I hadn’t gone back because why would you chase a ball with a stick when your mum was dead? I had loved it, and that love was switched off like a bathroom light, with a ping.

There were three of them standing between me and the door, talking to each other. I tried not to look, but I did anyway. They were just regular teenagers in their school uniform. I thought blue and the blue light shone round them all. It was as if they each had a blue light inside them that was only activated when I thought of the word. I closed my eyes and walked fast, right through the middle of them. Was I imagining the shiver?

I knew I wasn’t.

‘Oh, sorry!’ It was a girl, a real one, who must have been Year Seven because she was tiny. She was apologizing because I’d walked into her with my eyes closed.

‘Oh God, no,’ I said. ‘I’m sorry. I wasn’t looking where I was going.’

‘S’OK.’ She scurried away, waving to someone.

I pulled my backpack on properly, turned up the Idles on my phone, and walked home with the most confident strides I could manage because I knew that if I let myself stop I’d collapse.

Sasha was in the kitchen, looking from a cookery book to a pile of vegetables. She had always been a fan of junk food and famously hated cooking, and I laughed at the sight of her so far outside her comfort zone. It felt good to laugh.

‘Healthy-food time,’ she said. ‘How hard can it be, right?’