When I was little, I had an imaginary friend I only met on the beach. When dad was talking on the phone and didn’t have time to help me build my sand-castles, she would walk out of the sea, sit beside me and help me build moats and fill them with ravenous alligators, all the while letting her wet hair dry in the breeze, sometimes running it across my face to tickle me.

She would tell me stories about the people on the beach and why they were there, such as the lifeguard whose younger brother had drowned in a bathtub when he was my age, and the pot-bellied old man whose wife had died in a tidal wave seven years ago and who therefore engaged the sea in a staring contest every day.

Dad would then take me to get food, and my friend would waddle beside me, resting on her haunches and sometimes taking a polite but firm lick of my ice lolly. I loved how she enthusiastically clasped her hands between her knees when she did that.

When it came time to leave, she would wave to me and then walk back into the sea. When she was submerged up to her nose, her hair would float up around her, and it would suddenly get pulled into the sea when she submerged, like a dark jellyfish she carried around with her.