It is freezing here at night. Sophie draws her knees up to her chest and wraps her arms around her shins. The seat she is sitting on smells of damp, and apricot foam pokes through holes where insects have burrowed. She remembers folding this seat out into the bed that her and Callie used to share on holiday, snuggled down in their matching pyjamas. In the morning, they would shower in the communal bathroom, standing in cool, sandy water that had pooled in the shower tray from the person before. Callie would help Sophie wash her hair, never letting the frothy bubbles sting her eyes. Callie always helped her, and Sophie feels so many shades of regret as she thinks that if Callie hadn’t helped her that night she would still be alive today.

It had been a foul night. Rain flung itself at the windows like handfuls of tiny gravel, but inside Owen’s house they were warm and cosy, the radiators belting out heat.

‘Come on, baby. You know what it does to you.’ Owen offered her the rolled-up note.

‘I don’t do that any more. I thought you understood when we got back together? I’m staying clean.’

‘And I respect you for that. I really do. One last hit though. For old times’ sake?’

Sophie hesitated. Longing for the rush. ‘This is the very last time.’ She bent over the coffee table and sniffed hard before wiping the white residue from underneath her nostrils and curling up on Owen’s lap. She kissed him deeply as euphoria flooded her body. She was just sliding her hand inside his boxers when somebody banged on the front door.

‘Ignore it,’ muttered Owen as she froze, and he had put his hand on hers, urging her to carry on.

The thumping came again, louder this time.

‘They’ll go away.’ Owen pinched her nipple hard and she had groaned.

The letter box rattled open. ‘I know you’re in there,’ screamed a voice. Callie’s voice, and Sophie had scrambled to her feet, straightening her top. ‘I just want to talk,’ Callie yelled.

‘She won’t go away until you answer,’ Sophie had said, and Owen muttered furiously as he zipped up his fly and swaggered down the hallway.

Callie strode into the lounge, dripping hair plastered to her skull, eyes blazing.

She grasped Sophie’s arm. ‘We’re going.’

‘No!’ Sophie stood firm.

‘She’s not going anywhere.’ Owen stood in the doorway. ‘We were in the middle of something until you rudely interrupted.’ He grabbed his crotch and smirked.

‘What the fuck do you see in this loser, Soph?’

‘I love him.’ Sophie wished Callie would give Owen a chance and get to know him properly.

‘This. Isn’t. Love.’ Callie slapped her palm against her forehead in despair. Her diamond engagement ring glinted in the light, and all of a sudden, Sophie was sick of her perfect sister with her perfect boyfriend and perfect life. She grabbed Callie by the shoulders and shook her hard. ‘Leave me alone. You’re always trying to ruin things for me. I don’t need you!’ The words felt hot to Sophie as they spilled out of her mouth.

‘You heard her.’ Owen stepped to the side and gestured to the hallway with his hand. ‘See yourself out. We’ve things to do.’ Owen’s hand moved towards the zip on his trousers, and Callie sprang at him, pushing him backwards.

‘You fucking, fucking bastard.’

‘Get off, you mad bitch.’

Owen shoved Callie hard, and she fell. There was a sickening thump as she hit her head on the coffee table and lay motionless on the stained carpet. For a split second Sophie thought she was dead and the pain was so physical she thought she might be sick. Sobs ripped through Sophie but Callie pushed herself up and Sophie rushed to her with relief. The side of Callie’s face was red and puffy and her eye was almost shut; blood trickled from the corner of her mouth and Sophie wiped it away with her thumb.

‘Oh God. Callie. This was an accident. Right, Owen? You didn’t mean it, did you?’

‘’Course not,’ Owen said.

‘Soph. Please come with me.’

Sophie swallowed hard. She couldn’t look her sister in the eye. ‘Mum and Dad are happy me and Owen are back together. Why can’t you be too?’

‘Mum and Dad don’t know about this shit, that’s why.’ Callie picked up a white plastic bag of powder from the table, and Owen laughed. But it was a cold, hollow laugh.

‘I’ll tell you a story about “this shit” shall I?’ Owen yanked Callie to her feet and she whimpered and tried to pull her arm free, but Owen wouldn’t let go.

Sophie could see Callie’s skin indenting, could almost feel how hard he was pressing. Sophie was scared. Really scared about what might happen next and she knew she had to get Callie away from here. She picked up a bronze figurine of an intertwined couple she had bought Owen for their first-year anniversary and brought it crashing down as hard as she could on the back of his head.