"Trust me just this once - you are the opposite of ordinary."

She is the opposite of ordinary because she ties her shoes with strawberry liquorice laces.

She carries a key in her pocket which opens a box with nothing in and the only songs she listens to are nursery rhymes. She walks down the street humming hickory dickory dock and smiles at the people as they walk past. She only ever wears primary colours and always has on knee-high socks which don't match.

The postman knows her as Miss NumberEleven B, North Sea Road, Little Stramongate. The newspaper boy knows her as Vogue, Elle, and The Guardian (twice weekly; Saturday, Tuesday). The bus driver knows her as The Regular and the lady on the checkout till in the Co-op on the corner knows her as Always Coco-Pops But Never Condoms. But none of them really know her at all. To them she's just a fleeting smile and occasional wave.

She lives in a ground floor flat with a yellow door, with nobody but a canary in a cage for company. An old lady lives above her and every morning they both leave the house at half past seven. They exchange straight white smiles and the old lady says, "Hello Isabella."

"Hello Dora," Isabella says, and Dora asks after the canary. Isabella smiles and says, "We're definitely safe from gas today."

Every morning, whether it's a week end or a week day, Easter or New Year, rain or shine, she closes the yellow door behind her and runs down the pavement, with the 442 bus biting her heels. She races it to the bus stop and jumps on, red faced-

"Hello, return to Meeting House Lane please."

"Certainly, dear."

She gives the bus driver two pounds seventy five. The press of buttons, the cha-ching of the till, the "Thank you, dear." And then the whirr of the machine as it sticks out a tongue, and Isabella rips it off. She puts it in her pocket, exchanges a camera-flash smile, and goes and sits by the window.

She works as a waitress in a Café called Truly Scrumptious, opposite a Quaker Meeting House and a rifle shop. She takes people food all day but doesn't eat a thing, smiles and asks for orders but otherwise never says a thing, sees the odd looks and snide glances she gets but never does a thing. She waits patiently for time to push the day along and when it's five fifteen she hangs up her apron, smiles at her boss and leaves. She gets the 442 back to Little Stramongate, jumps off and walks to her front door. The canary tweets at her. Still safe from gas.

The milkman is in love with her.

He watches her every milk delivery day. He takes out his cart at four thirty and starts his route, and by the time he's reached North Sea Road, Little Stramongate, it's half seven and Dora and Isabella are coming out through the yellow door. He watches her as she runs for the 442, shoelaces bright red and edible, dressed like she just jumped out of a crayola packet. He keeps his seaweed eyes on her retreating back as he slowly puts three milk bottles at the foot of the yellow door. He counts it out in his head. One for her, one for the old lady and one for the canary.

The milkman is not an exceptional man; he's tall and young and fair-faced, not especially clever but not abominably stupid, funny but not a riot. He was brought up on a farm and he's one of those people who isn't a member of the AA because if his car breaks down then he'll know how to fix it; a realist, a let's-go-out-and-mend-the-fence-even-though-it's-half-five kind of person. He's spent his life doing very ordinary things and seeing very ordinary things and saying very ordinary things. He's always been surrounded by very ordinary people.

She is a refreshing change. She's the extra-minty chewing gum after a Sunday roast. She's the ice cold water at the end of a long bike ride. She's the cool breath of the fridge on an unpleasantly hot day. She's extraordinary.

He's watched her for years now, ever since she moved in. She fascinates him. She's dependable as rain in April; not once has she ever not been there, on her doorstep at half seven. Nor either has she had anyone else in her house, just her and the canary, and the old lady upstairs. The empty milk bottles are always out in the morning ready for collection. The money is always in the exact change and on the correct day. She always races the 442 to the end of the road and she never loses.

He likes to see her bright eyes as she opens the yellow door and looks up at the sky. He likes to see the way she smiles at the old lady who lives in the upstairs flat. He likes to see her hair trying to keep up with her as she runs for the bus. He likes the way there's always people looking at her and laughing at her but she doesn't seem to notice or care.

Today is a sunny Monday, a milk delivery Monday, just another manic Monday. The air is warm as toast and the sun is bright as custard, and Edward has decided to leave her a note. He spent the whole night with a pad of post-its and a biro, and by the morning he had a bin full of scrunched up luminous paper and thirteen words. I'm Edward and I deliver your milk and I think I love you. He's no Keats but he's never before been expected to be a poet. He could probably list the number of books he's read on one hand. And they're probably all by Roald Dahl.

He leaves the note under the bottles and runs away before he can change his mind. The wind ruffles its edges and the milk bottles perspire onto its surface.

He holds his breath for two days, tapping fingers, raw nerves, one hundred and seventy two thousand eight hundred seconds, two hundred and forty four thousand seven hundred heat beats. And then it's a wet Wednesday and he's delivering milk as fast as he can, a morning blur of bronzed hair and white bottles, "Here you go, nice morning isn't it, didn't you ask for that? Oh well have it anyway-"

And then at long long last he gets to the yellow door, and it feels like he's a pilgrim and this is the Vatican. The sun is smudged through the falling rain and the air is grey, like a faded painting, and North Sea Road, Little Stramongate smells fresh and alive. The raindrops are falling in random dots on the dry pavestones, little dark wet splodges here and there, gathering and merging. Her footsteps are echoing in the air and the rumble of the 442 is rolling out into the morning. The old lady is inching her way up the street and humming to Moon River.

There is a piece of white paper curled up inside an empty bottle on the doorstep. His eyes lock onto it and his heart grows wings and flies up to his ear. He jumps out of the milk cart.

Then he runs back to put the handbrake on before it trundles merrily off without him.

He trips his way through the falling rain to the doorstep and tips the rolled paper out with trembling fingers. He grabs both edges and pulls sharply. The paper rips in two and he frantically holds the two pieces together, a jigsaw of the heart.

One is one and all alone and ever more shall be so.

He stares at the paper and frowns, his eyebrows slanting down like confused knives into his face. He folds it and puts it back in the empty bottle, takes all three of them back to the cart. He puts the three more full bottles on the doorstep and around the neck of one of them he hangs a plastic Tesco bag. He bites his lip at it before turning around and hopping back onto his cart.

He doesn't really understand how he feels; it's as if someone's taken his emotions and put them in a food processor. He's just mush. All he knows is that she is going to be in his mind for nine tenths of the time until the next delivery day.

She gets off the 442 that afternoon and walks up her street, humming quietly, Jack and Jill went up the hill to fetch a pail of water. She smiles at the canary as it tweets at her through the window. She pauses to pick up the milk bottles; and sees the plastic bag.

Stapled to it is a note. Thought you might need these. The writing is broad and even.She looks into the plastic bag and pulls out a four-pack of strawberry liquorice laces.

A smile spreads across her face like butter on bread and she turns around as if she expects him to be there.

It's two days later and Edward is trundling along in his milk cart, which just won't go fast enough. The morning is warm, tingling with the promise of summer and the echo of ice cream vans. Birds are gathering in the sky and looping around each other, rising and falling and twisting and diving. The wind is whistling happily up and down the terraced streets, blowing through open windows and people's hair, pushing discarded newspapers along the road. The sky is a clinical blue, pure and bright.

He's left Greater Stramongate and is just turning into Little Stramongate. He keeps checking his watch to make sure he's on time, peering into front windows for clocks to check that his watch is on time, comparing those clocks to other clocks to make sure they're all on time. He's delivering quickly again, so quickly that his breath is coming in pants and his heart is going madly, pump-pump-pump-pump-pump. He turns onto the street with the yellow door and looks eagerly towards it, wide eyes and staggered breath.

Isabella is sat on the doorstep chewing strawberry liquorice and watching for the milk cart.

Dora is walking slowly along the road, watching them with clear grey eyes, a smile playing with the corners of her lips.

"Morning," Isabella calls, trying very hard to not be nervous or at least not look it. She blushes and chews the liquorice harder.

He slows down and draws level to her. "Morning," he says.

He smiles and she smiles and he stops the cart, picks up three bottles of milk and walks over to her.

"Thank you," she says, looking up at him and holding up the end of the liquorice lace, "I was running low." The sun behind him circles his head like a crown and it looks like he's glowing.

"That's okay," he says.

They smile at each other, an awkward I think this could be something smile, the kind of smile you give your future best friend after you've exchanged names and ages. She asks him if she can have a lift and he smiles and nods. He reaches down and takes her hand and pulls her up. "I'm Isabella," she says, curling the liquorice lace around her hand.

The 442 rumbles past and the canary calls through the window and Dora watches happily on the street corner. Edward opens the milk cart door for her and Isabella climbs into the passenger seat, pulls her knees up to her chest, smiles at him, blushes.

"Meeting House Lane, please," she says.

"Righto," he says, and twists the key in the ignition. They both buckle their seat belts and he looks down at her and smiles. He feels jittery and overwhelmingly happy, and she's trying very hard not to wiggle her legs in excitement.

The canary tweets happily.

Dora smiles as she hobbles around the corner.

The engine hums and the milk bottles rattle and they set off down the road.