After packing my suitcase with the sexiest outfits in my wardrobe, I wrapped Mary's present - A limited edition album from her favourite boyband. Knowing I was going to have to try on the fancy-dress costume I donned a pair of denim shorts and a loose t-shirt. I then laid my smart clothes on the bed, ready to change into, just before we left for Sir Peter's estate. I had to wait until seven o'clock so I put the kettle on.

I propped myself up on the bed and ran through a few ideas of what the costume might look like. I considered characters from films. There was Dorothy from the Wizard of Oz and Hermione from Harry Potter, both could be morphed into sexy outfits. However, I expected something more overtly sexist, like a maid's outfit or a nurse's, because those uniforms appealed to most of my old boyfriends.

Sir Peter had warned me politely, so I had to be prepared for the worse costume I could imagine. The minutes ticked by slowly and for the tenth time I wished I hadn't drunk as much champagne...

Finally, the doorbell rang, so I hurried out of the bedroom, then scampered along the hall, barefooted, and opened the front door. I was surprised to find a black guy in a grey uniform, standing on my doorstep. He was holding two medium sized black holdalls as though he was about to move in.

"When you've stopped gawking, can we come in, Sandy?" Emily was standing behind the chauffeur in deep shadow.

"Of course, come in..." I stood aside and let them pass.

My ground floor flat shared a drive with the one above. The chauffeur had parked his imposing, black multipurpose vehicle behind my car, so he wasn't blocking anyone. I shut the door and followed them down into the lounge where the big guy had dumped the bags in front of the gas fire.

Emily seemed to radiate power and domination as I watched her magnificent ass, tightly packaged in a black leather miniskirt, sashaying down the hall. Her shape was probably similar proportions to mine, but she was much taller and bigger boned. She was indeed a formidable woman.

She stopped at the door to the lounge. "I love your tree and decorations, Sandy. Did you do it all yourself?"

"Yes, Emily. I had a few hours free last weekend." I pointed at one of the bags as we entered the room. "Have you brought a selection for me to choose from?" It was a half-hearted joke.

"No, Sandy, the costume comes in two bags. Eric is going to empty the first bag and we'll give you ten minutes to decide if you'll wear it."

"Oh, okay, Emily. Do you want a cup of coffee while you wait?"

"No, I'll wait until we get to Grosvenor Hall." She sat down on the sofa to watch.

I could feel an intense thrill in the pit of my stomach when the big guy hunkered down and unzipped the first bag. Whatever was inside was black, for the material immediately bulged out of the opening. Then, my jaw dropped when he yanked the costume out and pushed the bag aside.

"Oh my god, it's an animal's pelt." I gasped.

"No, but it's a good likeness," Emily pointed out. "Eric, stand aside and let Sandy have a look at the suit."

Once I had space, I dropped to my knees and examined the 'costume'. The material was tough and stretchy and was covered with inch long black fur. It reminded me of the picture of Emilie's dog sitting on her desk. I lifted the suit up and discovered that the hind legs were the same length as the front, so it was designed for the wearer to crawl around on four very realistic dog paws.

The part that I was most concerned about was where the material fitted at the apex of my thighs. I discovered that it had a reinforced slot about four inches long which would leave my pussy and anus without any protection. There was a tail that seemed to have a spring of some sort to keep it down, possibly to spare my blushes.

I turned on my knees and pointed at the other bag. "What's in there. Emily?"

"The head. I don't want to get it out if you don't want to try the suit on. You have another five minutes, Sandy."

"Does the head cover my face?"

"Yes, it's a realistic Puppy-dog head."

I sat back on my heels and examined the pelt again, for that's what it felt like. Sir Peter wanted to test my decisiveness, so I had to make my mind up quickly. I was going to cringe with embarrassment during the whole party as I trotted around, acting like a dog, However, with my face covered, my humiliating reaction would be hidden from view.

"Okay, Emily, I'll do it. What happens now?"

"Eric will go and wait in the car while I help you on with the suit to ensure it's the right size and you're comfortable."

The chauffeur turned and left the room without a word. I waited until I heard the front door close, then I got to my feet and started to unbutton my shorts.

Emily looked around the room. "What sort of condition was the flat in when you finally completed the purchase?"

She gave me some advice on mortgages which was extremely helpful. "The kitchen needed an upgrade, otherwise a lick of paint here and there..."

She raised an eyebrow when I pushed my shorts down to reveal I wasn't wearing panties. I discarded the shorts and lifted my t-shirt off.

I had never stripped in such a manner, before another woman, let alone a black woman. She sat there, just a few feet away, staring at and examining my body. I couldn't tell whether she liked what she saw.

She sat forward on the edge of the sofa. "Come here, Sandy, so I can take a closer look at you."

I was surprised but not shocked, for I had been fantasizing about the woman for some time, and there she was sitting in my flat while I bared all. "Um, what for Emily? Shouldn't I be trying the suit on?"

"Sandy, do as I say," she said with a touch of impatience in her voice. "I only want to take a look at your beautiful body."

"Is this part of the test?" I asked after taking two steps toward her.

"Yes, everything you do now, having agreed to wear the suit, is of interest to us."

I stood close enough for her to put her hands on my hips. Her eyes wandered over my body, then she turned me slowly until I was facing her again. She moved her right hand and touched the short dark pubes on my mons.

"Most girls these days like to be glassy smooth."

I wasn't embarrassed talking about intimate matters with another woman. "Um, I trim my mons and shave my lips."

"Oh, let me see. Lift your knee..."

Talking and doing were two different things, but I wasn't fazed by her order, so I lifted my knee and held it up against my hip while she gazed at my pussy lips.

"Aren't labia beautiful things?" I nodded in agreement. "Have you ever performed cunnilingus on a friend or had a friend do it to you?"

I dropped my knee and shook my head. "No, I haven't. The opportunity has never arisen."

"So, you might?"

"Mmm, I suppose so. Is this line of questioning going anywhere?"

"It may be. Tell me. If I undressed, now, would you happily bury your face in my sex?"

"Emily, if you ordered me to, I would do it gladly, as an experiment. However, I believe in what's good for the goose is good for the gander."

Was she going to remove her skirt and panties and tell me to kneel and put my head between her thighs? For the time being I had to shelve my fantasy.

"That's a good answer, Sandy." She gently slapped my hip as though I was a naughty child. "Now let's see if the suit fits you."

The crafty PA had cleverly put me at my ease and made it far more acceptable to try the suit on. She had laid hands on me and broken the ice. I had the distinct impression I was not the first girl she cajoled into trying on a Puppy suit and wouldn't be the last...