Isa met them at arrivals on Thursday afternoon, smiling and saying, "Welcome back" and the kisses went on a little longer than courtesy.

Jean-Pierre helped Oliver with the bags.

The evening faded into food and wine and catching up as the four of them fell back into old rhythms.

Isa and Eira alone at the table, the men out on the balcony with their wine, the doors between them open as Paris continued outside.

In the morning, when Eira came downstairs there was an envelope on the kitchen table, propped against the butter dish.

Isa's butter dish on Isa’s table in Isa's kitchen with its copper pans and the window overlooking the courtyard.

All of it familiar, none of it hers.

Eira’s name was written across the front in a hand she didn't know, but it was addressed to the home of Isa and Jean-Pierre.

"Looks like somebody knew I'd be here."

Isa handed it to her, and she opened it, inside was a black card with gold lettering: a time, a place - The Salle des Miroirs. By special invitation only.

In English, so she could read it - Isa said she knew the place.

A half hour before the appointed time, leaving the husbands to their own devices, they left home together.

Arriving in good time, they were met by a doorman wearing a tuxedo who looked straight past Eira and addressed Isa with, "Bonsoir, Madame."

Eira gripped her clutch, noting that her heart was racing.

Isa squeezed her hand. "Good evening, Charles. Kindly speak English for the benefit of my friend."

"But of course, Madame. Your usual arrangements are in place."

Then he looked at Eira, noticing how she stood a half step behind Isa and asked them to follow.

He parted a heavy velvet curtain.

Eira saw a room that went on and on with panels of mirror from the floor to the ceiling.

Faces turned, and reflections turned with them.

Women were taking in the woman still standing behind Isa.

"Isa spoke to her, saying, "There's something I have to do darling; don’t wait for me."

And suddenly she was alone. The chill of the street left her as the warmth of the room took over: candle smoke, perfume, and … the unmistakable aroma of sex.

She found a chaise near an arched window and sat where she could observe.

Torches in sconces, mirrors multiplying everything, and women scattered throughout the place in every state of undress, wearing masks.

Some wore no more than a string of pearls.

The music was piano over a bassline, and it vibrated up through the floor into her chest.

A woman in a lace half-mask led another into an alcove.

In a corner she saw numerous bodies in a loose knot, one kneeling with her arms around another’s thighs as her mouth worked.

The piano stopped and the torches flickered and then, down the centre aisle strutted a woman in a deep crimson, off the shoulder velvet gown and corseted bodice with gold embroidery.

She wore a matching velvet cloak that pooled into a long train around her red heels with jewelled ankle straps.

A jewelled gold mask over her eyes, a heavy gem-studded choker, elbow-length red gloves, and a riding crop completed her look.

A voice announced her.

DOMME ISABELLA.

The room parted and bowed as she took the waiting throne in the centre and arranged her legs.

"Welcome, my ladies. Tonight, for the benefit of a certain person present, we speak English. Who's ready to play?"

Eira saw the head tilt, the set of the shoulders, and the eyes behind the mask, and the realisation hit her; she was looking at Isa.

Activities recommenced with women finding each other, masks freeing them to be someone else for a few hours.

Eira sat with her thighs pressed together and watched, then Domme Isabella stood, and the room went quiet again as she walked to where Eira sat.

She didn't say anything; she looked and held out one open palm.

Eira looked at the hand, then up at the mask.

She could stay a spectator or … she put her hand in the palm.

The grip closed, and her knees almost went.

She was led by the hand into an alcove decorated in red velvet and mirrors, with a low table and a chaise carved with flowers.

Domme Isabella sat her down onto it and kept pressing until her back met the cushions.

Without a word she knelt between Eira's knees, close enough that the heat of her was felt through the silk of her dress.

The crop traced up the inside of Eira's thigh, cold and smooth, past the knee, higher, stopping short of where she wanted it … the tip hovering there.

"Look at me." The crop tapped Eira's cheek, tilting her head back. "You're in my domain now and you're mine tonight. Tell me what you want, little one."

"I want …" Eira swallowed. "You to decide."

"Good." The crop came down across her inner thigh; not too hard but hard enough.

A gloved hand pushed hair off Eira's face, gentle after the crop, and pulled her forward by the back of her neck and kissed her.

Eira's mouth opened, and the tongue came in and filled it.

"Such a good girl." Domme Isabella sat back to breathe. "You taste like forbidden fruit; I think it's time we started."

"Isa."

"Not tonight, chérie. Tonight there is no Isa. Now stand up."

Eira stood, and the mouth came close to her ear.

"Before we go any further, you choose a word; say it and everything stops. No questions. Understand?"

Eira nodded.

"Say it out loud."

"Fjord."

A laugh escaped her. Domme Isabella's painted mouth curved. "How very Norwegian."

She drew a length of black silk from inside her gown and lifted it over her eyes and tied it with practised fingers.

Her sight disappeared. Everything else came in to fill the space: the bass through the floor, the rustle of the gown as Domme Isabella unhurriedly circled her, the crop at her jaw, her throat, her shoulder, never long enough in one place to anticipate.

"You've been so nice and polite, a woman who simply watches." The crop paused at a strap.

"It’s time for you to stop watching."

The strap slid off her shoulder, and when a gloved hand settled on the bare skin there, Eira let out a little sound she didn't recognise.

"There she is."

The second strap fell, and her dress dropped to her feet. She stood in her panties, heels and blindfold only while the air conditioning found her hardening nipples.

"Look at you, hiding this." A fingertip ran down her spine, and she arched into it like a cat.

Hands cupped her breasts and teased the nipples, and she felt the heat between her legs.

Her head tipped back onto Domme Isabella, her hips pushed forward into nothing.

She was turned by the shoulders and manoeuvred until the chaise hit the back of her calves.

The palm of a hand put her down. She sat, then lay back, and the velvet felt rough under her shoulder blades.

The crop flicked across her stomach, and she flinched.

The tip drew a line over her navel to the waistband of her panties and hooked under the elastic.

Eira lifted her hips and let them be taken down her thighs, her knees, and off her feet.

"Open for me."

She opened her knees.

Warm breath landed, then a flat tongue, the whole width of it, dragging slowly up from the bottom of her to the top.

When she came, she cried out, and Domme Isabella said, "That's one. How many have you got in you do you think?"

"I don't …" Her voice cracked. "I don't know."

"Then let's find out."

Back down she went, tongue circling, flattening, flicking, lips closing and suckling, gently, then harder, then gently again so Eira never got a rhythm to settle into.

Fingers pushed inside her, and her heels dug into the chaise.

Her hands flew out for something to hold, and a gloved one caught her, laced through and pinned her palm to the velvet beside her head.

"Stay with me. Don't go anywhere just yet."

She came again with her back bowed off the cushions.

Domme Isabella rode it out, fingers steady and tongue working gently until Eira went limp.

The hand kept hold of hers.

Then she straightened and turned her head to the dark, past the candles and lifted two fingers.

Eira didn't see, but she heard: unhurried footsteps on marble and then a second body close enough to change the air.

Domme Isabella spoke in French. The female voice replied, "Oui, Madame."

"Eira, meet Swan. She's been watching you and she's going to help me with your education."

The blindfold came off, and two masked women stood over her. Swan's mask was white feathers with a silver beak and black eyes; she was younger than Eira expected, and she was naked.

Smiling behind the mask, she took both of Eira's wrists and pinned them above her head with one hand.

Domme Isabella picked up the crop. "Now, start counting."

The first thwack landed across the tops of her thighs. "One." The second on the other thigh.

"Two." The third higher, on the flat of her belly.

The crop worked its way down, delivering small thwacks, each one followed by a warm hand caressing the sting away.

By the time it reached her inner thigh, Eira was twisting against the velvet.

"Open. Swan, your turn. Slowly."

Swan let go of the wrists. Eira's hands found Swan's hips and held on.

Swan slid between her legs and put her mouth on her pussy, and, there was no other word for it, she was greedy.

Greedy and unashamed, opening her wide and eating with a passion.

Domme Isabella stood back with her arms folded and the crop under one elbow, her eyes going from Eira's face to Swan's working head.

Eira came on this stranger's tongue and shouted "Isa" out loud when she did, and both women heard her.

Swan was dismissed with a kiss to the forehead, and Eira lay on the chaise with Domme Isabella at her head, stroking her hair.

Once she thought she might say the word, and a hand found hers and held it, and she didn't.

At some point she'd stopped being anxious.

It was nearly four in the morning when the taxi left them at the door on the rue de Turenne.

Isa had taken her mask off in the car and shaken out her hair, and now she was just Isa again, lipstick smudged and heels hanging off one finger.

On the landing, Eira stopped. "How long?"

Isa considered it with the same tilt of the head. "Eleven years. Jean-Pierre knows; he thinks it's very French of me."

"And the invitation? My name on the envelope?"

Isa smiled. "I've been waiting patiently for you to come back, Eira."

"Was I …"

Isa tucked a strand of hair behind her ear. "You were magnificent. And if you never want to go back, we'll never speak of it again. We’ll have breakfast in the morning and complain about bagatelles; nothing changes."

"I want to know everything about the club. I have questions."

"And I'll answer them in good time but for now, content yourself with knowing that we're adult women on private premises, an open secret in certain Parisian circles.

A gallery owner, a diplomat's wife, an actress, a widow, a barrister, a novelist.

Some are married; some are not. No advertising, no staff.

Invitations come from me."

"And if I do want to go back?"

Isa's eyes darkened, and Domme Isabella looked out of them. "Then we'll look forward to welcoming you, little one."

The package arrived on Friday morning, and Isa handed it across the breakfast table between the croissants and the newspaper without a word.

Jean-Pierre raised an eyebrow over his coffee. Oliver was engrossed in reading a news article and noticed nothing.

Same black card, same gold lettering. Saturday. Eight o'clock.

Under it, in tissue paper lay a white mask shaped like the face of an arctic fox with small crystals scattered across the brow.

"It suits you," Isa said. "Don't be late."

She wasn't.

Charles smiled as she approached and wished her good evening. He inclined his head, drew back the curtain and invited her to enter.

The heat, the smell and the bass were as she remembered, but this time she wasn't entering as a stranger.

A woman in a peacock mask touched her arm and said, "La petite renarde," and Eira guessed they'd been expecting her.

She walked down the centre aisle the way she'd watched Domme Isabella and her knees shook but she didn't stop until she stood at the throne.

The gown was crimson, and the mask was edged in black lace and garnets to match the crop lying across her lap.

"You came back," Domme Isabella said.

"You knew I would."

Laughter rippled out through the women nearest them. "So insolent. I see I have work to do."

The crop came up under Eira's chin. "Your word?"

"Fjord."

"Good. Kneel."

The marble was cold through her dress. The room watched, and much to her surprise, she found that she didn't mind.

Domme Isabella walked a slow circle. "Last time you were a guest. Tonight you're my apprentice. You'll learn what it is to give and receive and learn that the two aren't so different."

She stopped and held out the crop, handle first.

"Take it."

Eira wrapped her fingers round the jewelled leather; it was heavier than she'd expected and still warm.

Domme Isabella lowered herself onto the throne and extended one leg until the toe of her shoe rested beside Eira's knee.

"Show me what you've learned."

Eira's mouth went dry. She rose up and put the tip of the crop to the bone of the ankle, then ran it slowly up the silk of the stocking, the way it had been done to her.

Above the mask, the eyes closed for a moment, and the room was silent.

She slid the crop under the hem and along the inside of a thigh that opened for her and the stocking gave way to skin and then to something moist and she pressed the tip flat and held it there.

She felt the little buck of the hips more than she saw it.

"Well." Domme Isabella's voice had gone unsteady. "It seems the little fox has teeth."

"You did say I had a lot to learn so I thought I'd start with you."

She pushed the gown up over both knees, over both thighs to the hips and then, because she'd learned at least one thing, she didn't wait to be told.

She put her mouth where the crop had been.

Domme Isabella opened her eyes, and for a moment they just looked at each other.

Then she stood, took Eira's hand and led her through the parting crowd to the alcove.

The curtain closed, and for the first time it was Domme Isabella who waited to be told.

The alcove was as Eira remembered it: red velvet, candlelight, mirrors, the two of them reflected wherever she looked. The crop felt absurd in her hand.

"Breathe," Domme Isabella said. "You're not trying to become me; you’re trying to become you. What do you want?"

Eira reached up and unwound the black silk from her wrist, the same ribbon that had blindfolded her a week ago.

"Turn around."

She turned, and Eira tied the silk over the mask and heard her take a long breath.

"Now you can't watch," Eira said against her ear. "For once."

She walked her down onto the chaise and stood over her, just looking. The rise and fall of her breathing, her fingers curling into the velvet.

In the mirror she saw a woman she barely recognised, standing tall with a crop in her hand.

She started at the wrist, flat against the pulse then the inside of the elbow, then the collarbone where the gown had slipped.

She hooked the strap and drew it down until a breast came free, the nipple already hard.

She circled the crop around it.

"Do it," Domme Isabella said.

"Say please."

A beat, then. "Please, little fox."

Eira brought the crop flat across the nipple, and the sound Domme Isabella made wasn’t the sound of a woman in charge.

She did it again, and again, then threw the crop on the cushions and pulled the whole gown down and off leaving the stockings.

She knelt between her knees and kissed one thigh, then the other, working her soft lips slowly upward, licking, blowing and feeling muscle flinch and give.

At a knee she stopped and breathed, watching the hips tilt up after her mouth.

Domme Isabella asked, "Is this how it felt? Waiting?"

"Yes."

Then she kissed her pussy and drew her tongue in one long stroke from bottom to top, remembering the same stroke she'd been given.

She used her fingers and brought her free hand up over a breast and timed it together, and the long frame under her reacted to every touch and sensation.

She paused and let the waiting stretch until the voice under the blindfold spoke quietly with something that sounded like pleading, but she continued to wait.

"Bitch."

"Now you know."

She went back down with her mouth and finished her.

Domme Isabella came with her head thrown back, her heels dug into the chaise and both hands gripping Eira's hair, and the sound of it probably carried past the curtain.

Eira crawled up her and lay down with her cheek on her shoulder. The blindfold had gone crooked and one eye looked out from under the silk.

"Very good," Domme Isabella managed. "You're a natural and I resent it."

"High praise."

"You still have your dress on."

"I do."

"That seems unfair."

She pulled the blindfold off and lifted the crop. "I commend you on your first lesson."

Then she caught Eira's wrist, turned her and put her down on the chaise.

She took her dress off slowly, kissing skin as it appeared until Eira was naked and at her mercy again.

Back in its owner's hand, the crop said what it had to say across her stomach, her breasts, the tops of her thighs.

Eira counted aloud but lost count at fourteen and had to start over.

Then Domme Isabella pulled one of her legs over her shoulder and used her mouth and fingers until Eira held the edge of the chaise tightly, crying out in Norwegian.

"Come," she said, when the moment was right.

Eira came, and then, being the stubborn apprentice that she was, she came again.

It was then she noticed the curtain had been drawn back and in the dark beyond it, she saw faces.

Masks … a row of them: A peacock and a raven in black. Two swans, one of them surely the girl from the visit before.

A narrow gold mask, seven women in a silent half circle looking in at her.

Domme Isabella lifted her head but didn't turn around. "They've found us."

"You invited them?"

"They came to watch the lesson but since they're here and you've been very good, and since there are many of them and only one of me …"

She sat up and signalled.

They entered without a word and arranged themselves around the chaise.

"La petite renarde, you did not think Madame would keep you to herself."

"I … no. I suppose not."

"Then be a good little fox and lie still."

Seven sets of hands landed on her and divided her between them until no part of her was left unclaimed.

The peacock woman knelt above her head and kissed her upside down, slow and thorough, while two others, one in gold, one in a plain black domino, worked at her breasts with mouths and teeth until Eira understood how different mouths were, each with its own rhythm.

A hand stroked up the inside of her thigh and another came down it from the other side until her knees fell open on their own.

Domme Isabella stood at the foot of the chaise, crop in hand, directing traffic in quiet French.

She sent the raven down between Eira's legs and stood over her correcting: slower, there, use your thumb, no, she likes it high.

The raven obeyed and Eira came on her mouth.

After she did, the raven sat back and reached for something beside the chaise; a leather harness, a black cock through the ring of it, gel.

The room went quiet. The peacock drew Eira's head back and held it while two mouths closed on her nipples and two pairs of hands spread her thighs.

"Look," the peacock murmured, tilting her chin toward the mirror. "Look at yourself."

A woman in a fox mask, held open with a raven between her knees.

The raven pushed in, one long stroke and Eira's body lifted off the chaise.

Long, slow and deep, hands on her knees pulling them wider, every inward stroke dragging a moan out of her.

Two women held her hands, fingers laced through theirs. Two mouths still worked at her breasts.

The tempo increased as the raven drove harder; Eira’s cries climbed and she came on a stranger's cock in a mirrored room with six women holding her down.

They didn't let her rest, they turned her on her side, then onto her knees and took her that way, the raven behind her with a fist grabbing her hair and a thumb in her ass.

When they finally let her breathe, the peacock said over her head, "And you, Madame? Or are we only for the little fox tonight?"

Domme Isabella considered her. Then she put the crop down, stood in the middle of the room with her hands loose at her sides and said, "Begin."

They congregated around her and Eira, propped on one elbow, watched.

The raven stood behind her with her hips in her hands. Two others in front, four hands and two mouths.

The peacock pulled her back, biting her shoulder, holding her up when her knees went.

Then the raven rolled a condom on the cock and massaged it with gel.

Eira removed herself and the peacock sat back on the chaise with Domme Isabella's back against her breasts, her thighs spread open over the peacock's own and held wide.

The raven knelt between them.

Domme Isabella looked down at the cock between the raven's legs and then, at Eira.

The raven pushed in, and Eira watched her friend's mouth fall open and her neck arch back against the peacock's shoulder.

The peacock held her steady, both hands on her breasts while the raven fucked her.

Then Domme Isabella sought and found Eira's eyes and gave her a small nod.

Eira crossed the space, straddled her and lowered her cunt onto Domme Isabella’s mouth while the raven continued to pound her.

She came with her friend's cunt on her mouth and a room full of mirrors watching.

Much later they dressed and slipped out one by one, each pausing to touch Eira's hair or her shoulder on the way past, until it was only the two of them.

Eira's head lay on Isa's shoulder, Isa untied the mask and let it drop.

Her face was visible, flushed and smudged and laughing quietly at nothing.

It was the first time Eira had seen it bare in these walls.

"You're not supposed to do that in here."

"I make the rules, dear, and I wanted you to know who you were with."

"I knew," Eira said. "I always knew."

Oliver made breakfast just like he did every morning at home and saw no reason why Paris should interrupt the routine, and nobody argued, so when Eira came downstairs at half past ten, the kitchen smelled of cardamom and butter and Jean-Pierre was on his third waffle.

"There she is. You two were out late."

"Isa wanted to show me a club," Eira said, sitting down carefully.

Isa didn't look up from her coffee. "A ladies' club near Le Marais."

Oliver slid a waffle onto Eira's plate. "Brown cheese?"

"Yes, please, strawberry jam too."

Jean-Pierre poured her a coffee.

"You look well rested, Eira."

Isa nearly choked.

"You all right?" Oliver thumped her on the back.

"Fine … went down the wrong way."

Later, Jean-Pierre had booked a brasserie on the Île Saint-Louis, the kind with Vichy tablecloths and a view of the river and they settled in for the sort of Sunday lunch the French measure in hours.

Oliver and Jean-Pierre talked about sailing. Isa ordered wine without looking at the list.

By the cheese course the conversation had drifted back to the trip.

"I was thinking we should stay longer," Oliver said, swirling his glass. "There's more I want to see. And you love it here, Eira."

"She does." Isa got in before Eira could. "She's discovered a whole new side of the city."

Jean-Pierre coughed into his napkin.

"Has she?" Oliver turned to his wife, delighted. "Which side?"

Eira opened her mouth then closed it. She knew she’d tell Oliver everything, they had no secrets, but not right now.

"The nightlife," she said.

"A change from the routine," Isa said.

"You've never cared about nightlife before."

"That's true, but it's Paris, and it's different." Eira reached for her wine.

"Well, let's stay longer then. You can show me the nightlife, and I can see the parts of Paris you've been keeping to yourself."

She glanced sideways. Isa was watching, her smile held carefully in place.

Jean-Pierre began a story about a boat he'd once owned in Brittany, and Oliver leaned in.

Under the cover of it, Isa put two things in Eira's lap.

The first she knew: black card, gold lettering. The second was small and warm from Isa's hand.

A gold pin no bigger than a fingernail, the Venus symbol with a tiny crown above the circle.

Eira's thumb found the edges of it under the cloth and looked a question sideways.

"The card you know," Isa murmured, lips barely moving, eyes on her husband. "The pin is for the ladies."

"What is it?"

"What we wear. Small enough that nobody notices, but those who know, know.

A gallery owner might stand beside you at a vernissage, see it on your lapel, and you'll exchange a smile and nothing more.

That's the whole point; the pin is our secret."

Her hand stayed in Eira's lap a moment longer than handing over the items required.

"It means you're one of us. Not a guest, a member. It isn't given to everyone and it's never given twice, and it's never spoken of outside the Salle. Wear it on a scarf, a collar, a bag strap, a light chain."

Eira closed her fingers round the little gold Venus.

The waiter brought coffees and the light moved across the tablecloth.

Eira put the card in her clutch and kept the pin in her fist, and only later, walking back along the quay with the four of them strung out in a loose line, did she fasten it to her coat collar.

"So we're agreed on staying?" Oliver said.

Eira smiled at him and then briefly at Isa.

"Yeah, why not; though I suspect French culture has more to teach us than we've got time to learn."