Apparently, perfection has “never been more attainable”. Figleaves.com, the lingerie website, has started selling padded shorties (granny pants with two round foam buns inside) to give girls with a small arse, or the wrong arse, or whatever, some “sexy feminine curves”. The shorties, they claim, are a recession-friendly alternative to having thousands of pounds-worth of Macrolane injected into your buttocks. These shorties are only 30 quid!

It is all tush, of course. One of the best things about bottoms, the aspect of them that gives them pre-eminence over bosoms and legs, is that they can’t be faked. Tits you can pump full of silicone. Legs can be buffed and smothered in St Tropez and are, well . . . legs are just legs. Bums, though — bums you can see and you can feel. And, for girls, they are the thing we all have in common. Not just having one, but feeling like you have the wrong one.

At least, I’ve never liked mine. In the 1990s, when Lycra leggings were standard, it was cardigan-tied-around-the-hips time. There were bum clenches at the bus stop and bouts of swimming 20 lengths. Combat trousers were a blessing — for a moment. J.Lo can have her hip-swinging cheeks, tiny Kylie her perfect rump, but for me, peace never came. These days, I try not to think about it.

Men do, though. Men think about bottoms a lot. I squirm at the thought of the wince-inducing conversations I’ve been privy to about the classic English bottom. Which does make you wonder why I agreed to uncover mine, augment it with a “one-of-a-kind, star piece of shapewear” and put it on display, just for a day. What was I thinking?

THE JEANS

Of course, the impact of a bottom isn’t decided only by its size, but also by the way you frame it. In the olden days, a bottom was judged by how it looked in 501s; now, my friends, there is a pair of jeans for every bum. The big question, of course, is what of spring 2009’s “boyfriend jeans”? A bit of batty is better than none in order to not look like your boyfriend.

Instead, I take the tightest skinny jeans in the shop. On my way home, I find myself slinking past a building site, from which appear, like a vision, two 6ft 4in builders. Hello, Billy, hello, Greg, are you bum men? It turns out they are. “Big or small?”

“Big,” says Greg, with a slow smile (he’s delicious, so I don’t mind). “More to grab.”

THE LIBRARIAN LOOK

Some of the cleverest women in history have had bounteous backsides — they’ve just kept them covered. Not so my friend Camilla. A curvaceous glamazon with a mind like a steel trap, she would never dream of hiding what nature blessed her with.

I try out her look myself. To a bookshop to browse through Wharton, Isherwood and Auden. It is a shame that I’m so roundly ignored. Is the brazen display of intelligence and booty so rare that when both do come along, people don’t know what to do with them? Or am I convincing nobody?

More luck at Arthur’s in Dalston, the friendliest caff in London, run by Arthur, who is in his mid-seventies. Arthur is having a rest upstairs and “won’t be disturbed”. I ask a table of men tucking into ham, eggs and chips. Big or small? Patrick says: “Small, quite small. When it’s big, it goes out of shape.” Steve says: “J.Lo’s a prime arse!” Jennifer, serving behind the counter, chuckles and says: “You’re a prime arse!”

THE VERY TIGHT DRESS

I think we all know what the hot number of the season is. The Hervé Léger bandage dress sings for its supper. Overt sexual signatures can be the hottest thing in one context — and the coldest in another. Tonight, the girls at the indie night White Heat in Soho are mostly wearing little shorts, lumberjack shirts and DMs.

Three boys from Ealing agree that they’re fans of the petit derrière (but they are only 18 and haven’t yet discovered the joys of a womanly shape). Dave and Julian, in their early twenties, stay on the fence. “Not too much, not too little,” says one who, I’m guessing from looking at him, might be grateful for any, whatever the size.

Bored and embarrassed, I head for The Shadow Lounge, where Tasty Tim, an original gender-bender offender, with a giant mohawk touching the ceiling of the DJ booth, is holding his disco night, Tasty Tim’s Salon.

Boy, have I come to the right place. “You’re gorgeous and delicious,” says a pretty young queen who claims to be a pop star in Malta. “What are you wearing, darling? I love that dress, you’re a goddess.” And I’m twirled around the dancefloor.

“If you’ve got it, flaunt it,” says Tim. “And if you haven’t, accessorise. It’s about smoke and mirrors for all of us, darling. Winches and pulleys!”

I couldn’t agree more.

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