‘Tabby is in the final year of her clinical psychology doctorate,’ she explains, ‘and will be with us at the unit for the next six weeks. I’m sure you’ll all do a great job of making her feel welcome.’ A ripple of greetings works its way around the group, but Katherine doesn’t bother adding to it. She’s already met Tabby, at lunch the day before. The not-quite-a-doctor had asked to sit next to her in the dining room and Katherine didn’t have much choice but to nod. Tabby had curled her long blonde hair around her ear and shrugged at her good fortune to have found a spot in the less-than-half-full room. But Katherine can’t blame the psychology student for planning the encounter. Who wouldn’t be curious about the girl in bandages brought here by the police?

‘It’s lovely to meet you,’ Tabby says to the group. Then, excruciatingly, she shifts her gaze. ‘Although Katherine and I met yesterday, didn’t we?’

Everyone in the room turns to look in Katherine’s direction. Instinctively she puts her hands up to her face, hiding her shame, or maybe just the red-raw skin around her mouth and chin. Her eczema is like a rat. When everything good in her life dies, her skin disease continues to thrive. ‘Yeah,’ she mumbles, silently begging for that to be enough to halt the exchange. It’s her gaoler who comes to her rescue.

‘Great,’ Dr Sharp announces, drawing her hands together, and producing a muted clap that Katherine doesn’t think was intended. ‘Of course there’s no pressure to say anything this morning, but does anyone have something they’d like to share? And please, everyone, remember that this is a positive space,’ she adds.

With her head low enough to avoid all eye contact, Katherine scans the circle of her peers. She hasn’t attempted conversation outside the group – she knows that she’s incapable of making friends; what happened with Becca is proof of that – but they all know her story because she blurted it out in only her second meeting. She’s not quite sure why she did that. Maybe it was the sedatives loosening her tongue, but it felt more like self-flagellation; wanting to see the horror, the disgust, on the faces of this rag-tag group of teenagers with a variety show of mental health issues.

‘Um, could I say something?’ Everyone turns towards the ghost-like girl sitting closest to the door. Her pixie-cut hair is dyed so blonde it almost looks blue, and her ears shine with tails of silverware.

‘Of course, Molly. And take your time.’

‘Thanks.’ Molly blinks at the clinical psychologist. ‘In my one-on-one session, I talked about why I self-harm. Not the big why,’ she says, raising her hands and flickering her fingers, ‘not the existential reason why I hate myself. But the smaller why. The pleasure it brings.’