Harriet Walker: 'Nothing brings out my alter ego quite like a 'new house party'

The house party. It's the new not-quite-going-out, so you don't have to feel guilty about anything that happens at one. "Look," you can crow to similarly smug attendees, "I'm not flinging money over a bar in a trendy nightspot! I pre-mixed my gin and ginger ale outside in the street."

The "old house party" was the sort you would tend to have when your parents had gone out. I tried a couple of times, but was never convinced that me and two same-gender friends of whom my parents heartily approved really made the grade. The OHP ended with a suburban mother shouting, "Get out of my flower bed, young lady!" At the "new house party" there are no flower beds, because it is usually held in a block of flats or the garden has lain fallow for so long that it's now indistinguishable from the pavement.

But the problem with a NHP is that you're not bound by the same social codes enforced at clubs by men in Puffa jackets. Last weekend I met a guy who couldn't stand up straight because he'd tried to slide down a tiled roof the night before. "We'd just had a cucumber-eating contest and I felt so full of beans," he admitted over a cup of warm gin and flat tonic.

And whenever I go to a house party I unwittingly unleash my inner Northern girl. I've beaten her into submission enough to always wear a coat when I go out these days, but she's attracted by the prospect of cider sipped from a plastic cup. "Look at yew, lass," she says as I'm getting ready, "wi' yer 'air all neat. We'll take that down later, won't we? And this skirt looks purfect fer tuckin' into yer pants on't danceflewer."

Sure enough, I found myself propelled by my inner Northerner on to the "dancefloor" (the patch where the coffee table normally lives). "Go on, love," she insisted, "tek these bluddy tights off, they're too 'ot." So I did, and I flung them under the sofa. House parties are prime territory for sartorial change – my friend had one last month with a Rubik's Cube theme. "You were supposed to arrive multicoloured and then swap clothes until you were all one shade," she explained. "But loads of people just ended up naked."

I changed my own clothes last weekend as it turned out; all the buttons popped off the back of my dress, as if my inner demons were being exorcised by all the cheap booze. The next day I woke up cringing at those antics I could remember. "It's so funny how your voice goes all posh when you're drunk," my boyfriend said. "Brilliant," I thought, "no one knows the truth." "Do they 'eck as like," retorted my hungover inner Northern girl, as she tried to peel her false eyelashes off the pillow.