One hundred and fifty square feet of threadbare carpet, off-magnolia walls and an anonymous cityscape demarcate the scene of my transgression. The room service menu on the bedside is dog-eared. From where I kneel, on the floor at the foot of the tired bed, I see a stain on the wall form a Rorschach test in which the outline of a haggard face turns towards the corner of this hotel room as if the scene within has become unbearable to behold.

So why am I here?

I think back to the middle of last month. The envelope square in the centre of my desk, where the keyboard had been before I went for lunch. The immaculate cursive script that spelled out my name on the front. And inside, the single slip of paper showing one solitary imperative, in neat capitals: SUBMIT.

At the time, I stuffed the note, the envelope and the whole idea deep to the back of my desk drawer. Some office clown playing a prank.

But on each consecutive day, a new note, in a new location: each with the same stylised handwriting on the cover, but with a different exhortation within: SURRENDER YOURSELF, read one; LIBERATE YOUR BODY FROM CHOICE, another. KNEEL BEFORE YOUR MASTER.

What was this game?

By the time the envelopes began to slide beneath the door of my apartment late at night, my mind was frenzied. Rushing to the door, I saw only empty corridor through the spyhole. My hands shook as I tore at the paper for the notes within.

The notes delivered straight to my home took on a different form from those I'd previously discovered at work, or in my purse as I went to pay for my coffee. From these envelopes slid quality cardstock, each plain postcard embellished with fine ink sketches, the work - I had to admit - of a skilled artist.

Long past midnight, on one of the occasions I had found myself lying awake turning the mystery over again and again in my mind, unable to rest, ears straining for noises beyond the front door, I rose suddenly from bed and made my way into the kitchenette where the cards lay arrayed across the breakfast island.

I picked up the first and held it closer to the under-cabinet lighting. The black ink depicted the figure of a woman, drawn in quick pen strokes, kneeling, with slender arms pulled back behind her, her hands bound behind the small of her spine. Simple lines traced the curve of her naked breasts.

I reached for the second card. Again, the figure was that of a woman: breasts, hips, ass described in fluid inky curves, though this time her slender neck bore a dark collar, with a linked chain that pulled tight to the edge of the card.

Third, fourth, fifth and sixth cards repeated similar scenes; sometimes the woman was drawn from a viewpoint high above her head, her face reclined upwards, gazing up blankly at the unseen viewer. Once, drawn from behind as she half-knelt, half-stretched out, her thighs led up to an exposed ass, just a hint of her pussy revealing itself beneath.

The last, most recent card shook in my nervous fingers. A portrait, from shoulders up, of the same woman. Viewing it again, I shivered as I had the first time I saw it. For all the limitations of the medium, this woman was most definitely me, the artist capturing exactly how I wore my shoulder-length dark hair, the little beauty mark just below my right eye, the angle of my cheekbones. In my eyes, looking back up at me from the card, the most exquisite, wide-eyed acceptation of my fate.

So absorbed in studying this remarkable likeness of my face, I jolted back into my apartment at the sudden sound of something slipping beneath my front door. I raced to it and flung the door open, desperately - nothing but the familiar stillness of the communal corridor. I turned back inside the door and closed it, pressing my back up against it and considering the small envelope that lay at my feet.

Finding the courage at last, I bent down to lift it from the floor. Sliding a finger under the seal, I edged my way along until I could shake the contents out into my palm.

A hotel room card. A small slip of paper with the address of the hotel.