“I think it’s because of this blood brothers pact Kit and I used to do with one of our friends,” Thomas says, blowing out smoke into the wind and away from us. His voice is low, and he scoffs then shakes his head. “We were idiots, we didn’t piece it together for ages. But he had always talked about the songs and how beautiful they were, and then one day after we first did the pact, I could hear it too. Have ever since.”

“I can’t believe that worked.”

“Blood oaths are weird, old things,” he says, dragging on the cigarette again. His voice sounds distant, detached. I wonder if he’s doing it on purpose. I wonder if he knows it makes him sound like a twat. “You never really know what you’re getting into with them.”

He turns and faces away from the ocean and leans back against the railing. The wind picks at his hair and the sliver of the moon reflects in his glasses. The washed out colours of the night make him look deathly pale. Like the colour of seagull shit.

His face distorts into a grim expression and he lets out a dark laugh that billows with smoke. “I don’t fuck with those things now.”

I don’t know if he expects me to respond. I knew they’d done some kind of a blood oath — Kit had told me — but I only knew about the one they did when they were eighteen, the one that makes Kit quiet and sad when he thinks about it. The one that I would never, ever feel comfortable taking with another person.

I didn’t know they had a history of it. I don’t know why I keep being surprised; there are a lot of things I don’t know about Thomas and Kit and their life together before Thomas left. But somehow over the past few years, as Kit has become my best friend, he’s started to feel like mine. Finding someone who knows a different Kit — a pre-me Kit — feels odd.

“It’s my herd that’s singing,” I say, pushing past Thomas’s bad mood and shaking off the tiny curls of jealousy. Who cares if Thomas knew Kit first? Kit likes me more now. “They’re asking if I’m coming back.”

“So you’re from Kit’s… er… herd? Or rather, the same herd his mum was from?”

I stare at him.

“Do we look like we’re related?”

I kind of thought Kit would have gone for someone smarter than this. Kit and I look nothing alike — our human appearances are completely different races, for starters. His dad met his mum while travelling in the Philippines, so we figure his mum had to be from Pacific waters.

“Oh. No, I suppose not. He’s more — well.” Thomas pauses and clears his throat. “I don’t know how the selkie to human thing works, sorry.”

That seems like an understatement.