‘Ros,’ Sumi wedged her water bottle under her armpit and took both of my hands in hers. ‘There is only water. You will survive, you will dance and you will feel amazing. We need to seize these moments while we can. One day, we’ll have different responsibilities, we won’t be able to randomly nick off to a disco without a care in the world.’

‘We won’t?’ I asked. What was she talking about?

‘We will not,’ she confirmed. ‘Trust me, you’re going to love this. And if you’re very good, I’ll buy you a Nando’s on the way home.’

‘Won’t Nando’s be closed on the way home?’ I asked, allowing her to lead me towards a heavy black curtain.

‘Dark Disco ends at nine,’ she answered. ‘You’ll be home by ten, asleep by eleven and I swear it’ll be the best night’s sleep you’ve ever had in your life. You can thank me tomorrow when you’re incredibly grateful not to have to deal with Lucy’s baby-mama friends with a hangover.’

‘I don’t think I’ve been dancing sober since I was fourteen,’ I said, weirdly nervous as I handed my backpack over to a much friendlier-looking woman, standing behind a folding table.

Sumi snorted with laughter. ‘It’s just dancing, Ros, not shagging, which you definitely want to be drunk for. At least the first time. Or for the first three years, depending.’

I followed her through the curtains into a small vestibule where the music suddenly became much louder. I had to find out what kind of curtains these were, I thought, fingering the heavy velvet with admiration. Maybe they’d help class up the shed a bit.

‘My name is Jeremy, I work here at Dark Disco and, before I let you in, I’m going to run you through the rules,’ said a mystery voice. I could still see Sumi’s outline and a few stray chinks of light found her heavy silver necklace, covering her in stars. ‘Once you get inside, it’ll take a minute for your eyes to adjust to the low light conditions. Until they do, we suggest reserving your big dance moves. There is likely to be some accidental bumping into people but we do not condone unwelcome touching—’

‘How will we know the difference?’ asked a male voice.

‘Oh, you’ll know,’ Sumi replied before Jeremy could.

‘If you are touched in a way you do not find acceptable, in the first instance, please inform the person touching you that it is unwelcome as it could still be accidental. If it continues—’

‘Kick him in the bollocks?’ I suggested.

Sumi held up her hand for a high five which I just managed to hit.