The flat is warm and its windows fogged. It smells of cigarettes, hash, roasting turkey, and clementines. Four stuffed chairs and a two-seat sofa crowd the sitting room. They are draped with throws and fattened out with cushions. Framed and unframed pictures cover the walls – charcoals, oils, gouaches, lithographs, sketches of whom I presume to be family and friends, and souvenir postcards of everyone from Longhi and Moser to Grimshaw. The room was once two rooms but was knocked through, and last night was cleared of the bicycle, laundry, post, and recycling that are ordinarily here. All of the books and vinyl records have been tidied away. Near the French doors to the yard at the back is a table laid for a meal, and crowded by seven mismatched chairs. Everything here is like that: clothes, furniture, cutlery, crockery, records and books are dog-eared, dusty or rusty or scuffed. But it is cosy – made cosier still by the dark, red-painted walls, the coal fire in the grate, fairy lights, and the six foot bough of long-needled pine affixed to the ceiling where a wall once separated the rooms. Homemade paper snowflakes and chocolate coins dangle from the bough. They tantalise me. Everything here might be old and worn, but it's new to me. I only arrived three days ago and already it's Christmas, so it's been a lot to take in.

Of course I sniffed around. The flat is Belinda Bell's. Belinda is slender and small, with hazel eyes and a strong jaw. Her flat is shaped like a squared lowercase letter 'd', lying flat on its back. The bedroom and box room, from where Belinda runs her eBay shop, are adjacent to each other upstairs, on the first floor, as is the bathroom, an extension at the back of the house that forms the stem of the letter 'd'. The kitchen is directly below the bathroom. It is narrow and has an acorn-brown lino floor, a brown-spattered, old gas cooker below a window looking onto the little yard in the back and cabinets you could hide inside. When the half-size refrigerator clicks on it vibrates in e-flat and the magnets on its face describe patterns as erratic as butterfly paths. Belinda has been in the kitchen since sunrise. Chopping and boiling and stuffing and seasoning and basting. Just before guests began to arrive at three she raced upstairs to change for dinner. She is wearing a green, velvet, ankle-length dress with seven buttons on each sleeve, and a high, lace-crested collar. Her hair is swooped up in an onion-shaped pompadour that shows off a grey streak at the front. The grey streak is the first thing you notice (she is only thirty-eight), otherwise her hair is the hue of a dirty copper coin. It's getting on my wick that she's introducing me as Jarvis instead of Geoffrey Cantor (always the full four syllables, thank you very much) as I've been called all of my life. Next person who comes to the door and I'm gone. I don't want to be here when everyone twigs that Lucy isn't coming, when they realise she's disappeared.

Lucy ... oh, Lucy. You were built for the stage, for the opera, a Wagnerian soprano, with your big hips and chest, your tragic eyes, wide face, wide mouth and big arms – arms that seemed to pull at the air. We never met. But I know about you through The Glaring. I know where you lived and that you ran The Bitch and that you cycled everywhere, even in the rain, and fed the neighbourhood cats who came to your rooftop window. I know that you never asked for help but always offered it. I know you were a virgin, and I know the day you met Him. Belinda was there too. But to her He was just some old man.

It was late afternoon, the 1st of December. Belinda was rolling a cigarette in front of the Dorset. You were trudging up North Street with six shopping bags, rather resembling a powerlifter in the early stages of the clean and jerk. In one bag was a pair of ankle boots from Oxfam and three pairs of woollen knee socks. In another was your horde from the Saturday Market: a pewter letter opener (Secessionist, you thought), a rosewood box probably once used for pens or pins but now good for catnip or weed, a metre of Victorian lace and thirty-six un-inflated balloons. In the three cloth bags were your groceries, a bottle of disinfectant, kitchen roll, and a large scouring sponge. The air was icy. Christmas lights, hung earlier that week, twinkled and blinked. It was one of those wintry afternoons that feels like it belongs to an old photograph or film. The sky was dark; the snow was white. It didn't feel like Brighton but somewhere belonging to the cold, somewhere borne up from the past. A city like Budapest or Prague, with its understorey of secret police and vanished faces. You smiled at how your breath fell before rising and disappearing against the cold, hard darkness of the sky. Then, catching sight of the gulls circling in the high distance, you crunched hurriedly across the street in little Geisha steps. You would have kept going but you spotted a five-pound note, damp and partially obscured by the snow in front of the Dorset. You picked it up.

'Your round then,' Belinda said, simultaneously lighting her roll-up and, reaching behind her, whacking on the electric heater above her head. She was seated at a small, zinc-topped table near the door. There were two dozen or more people huddled in small bundles or at the other tables in front of the pub, and many more passers-by. You laughed and kissed Belinda on each cheek. Then you welled up. You tried covering your eyes but the bags were too heavy for you to lift your hands to your face. Dropping down in the chair opposite Belinda, you stared upward, trying to suck in the tears. Crying embarrassed you. It wasn't your way.

Belinda slitted her eyes. 'Either you've been fucked or you're in love.' She ashed and dragged meditatively. 'If you've been fucked, it wasn't by me, so I don't want to know. But if you're prepared to admit that you're in love with me ...' She blew a smoke ring and rhythmically pushed her finger in and out through it. 'Then, my darling, we can talk.'

You laughed again; the relief of it dried your eyes. You hadn't kissed anyone for four years, since you were twenty-eight, other than the night three years ago when you met, and snogged, Belinda. She was working on the coat check at the Hanbury. You were drunk and had lost the ticket for your coat. When you tried to collect it, Belinda flirted with you (later she confessed because she knew you were straight and wanted to see how far she could go). You flirted back (you thought why not). A bargain was reached. You kissed over the countertop. Belinda held your face and you held hers. Someone cheered. You got your coat – and an instant friend. Belinda was one of your closest. You knew that; you know all of this. But you don't know that she almost saved you. You should know that too, in case, like Persephone or the hiccups, you come back.

One of the barmen came and took your order. He had chunky glasses and a glistening quiff. You asked for a mulled cider. Belinda ordered a large glass of red and batted her eyes. The barman pretended to not notice and turned away. Archie, the Dorset's tabby, hopped down from a barrel by the door and inspected the shopping bags at your feet, poking his head in each. You toed the one with the rosewood box out of sight and under your chair. The box was your Christmas present to Belinda. It delighted you to think of the double-entendres she'd make when she opened it. You had a few planned yourself. Archie leapt onto your table and...