The change that Charlie had seen in Erin since they started their sessions with Yvette was rapid and, to him, a little bit astonishing. He had always loved their time together in the bedroom, where Erin was generally game for dirty talk and for exchanging fantasies and for light experimentation. Outside the bedroom, however, she was what Charlie might call reserved.
That seemed to be changing.
For as long as Charlie had known her, Erin carried herself with stylish understatement, beautiful if you happened to look, but rarely doing much to draw attention to herself. This was still the norm when going about her daily business, as she still wore her cashmere turtlenecks, her elegant cardigans, and her tightly coiffed hairstyles. It was the same when they spent time with friends.
When they went out just the two of them, however, it was an entirely different story. Erin's necklines were getting lower, her hems higher, and her lack of underwear more frequent and more obvious.
On Wednesday night, for example, they had gone for a walk and stopped for lattes on the way. Erin wore a flowery sundress, much like the one that Yvette had dressed her in when they went to the Cattail and she wore it without a bra so that her breasts jiggled slightly as she walked.
At the cafe, she had hemmed and hawed over her order, leaning forward on the counter to read the menu on the chalkboard against the back wall, which Charlie knew was an act. They went to that cafe all the time and Erin eventually ordered the same thing she always did. But her little routine did furnish the barista behind the counter with a clear view down her dress and Charlie chuckled internally as the young tried valiantly -- and rather unsuccessfully -- to keep his gaze politely north of Erin's chest.
"Did you see him checking out my tits?" Erin asked with a mischievous smile as they walked down the street with their drinks.
"I did," Charlie replied. "You didn't give him much of a choice."
"I don't think he minded," Erin said. She scrunched her nose and grinned. "I can't believe I did that! Can you believe I did that? Were you jealous?"
Charlie smiled at his wife.
"I thought it was pretty hot, actually," he told her.
When they got back to the house, they had barely made it inside before Charlie grabbed his wife and kissed her hard, pressing her against the wall. They left a trail of clothing up the stairs as they tumbled into the bedroom.
They fucked each other fast and hard, moaning and teasing each other with their filthy talk.
"Ungh -- yes, baby, fuck me, fuck me like David did," Erin moaned. "You liked watching that, didn't you?"
"Fuck, it was so hot," Charlie panted as he thrust in and out of Erin's pussy. "Did you like watching Lexy ride me?"
Erin desperately affirmed that, yes, she had indeed gotten off watching the busty brunette fuck her husband.
They came together moments later, and Charlie loved the feeling of Erin squeezing him as he poured his cum into her. Afterwards, they cuddled lazily, oblivious to the dampness of the sheets. Erin drifted off to sleep quickly, but Charlie lay awake for several minutes thinking about the last couple of weeks. He wasn't sure what it was that Yvette had managed to awaken in his wife -- or himself for that matter -- but he sure wasn't complaining.
He could hardly wait for their next session.
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It came a few days later and Charlie found himself again in the changeroom at the studio staring at a handwritten note from Yvette and trying to figure out what he was supposed to do.
The instructions were simple enough:
"When you are ready, come into the studio dressed only in what you find in the basket. -Y"
However, there was nothing in the wicker basket but four padded leather cuffs. He put them on his wrists and ankles and then stood for a minute, feeling strangely more naked with the cuffs on than when he was wearing nothing at all.
He noticed that there was a cotton robe hanging on the wall by the door and began to put it on. But as he started to pull his arm through its sleeve, Charlie paused. It was the same sort of robe that he had worn in their first session. These seemed to be fairly standard-issue for the studio -- Charlie had seen a pile of them in a laundry hamper in the hall as he came into the changeroom. The soft, deep black material of the robe fit the vibe of the place, in any case.
But it wasn't in the basket.
Charlie had learned that Yvette demanded precise adherence to her instructions and her note had said to wear only what was in the basket. Was it an oversight? A bit of imprecise language on Yvette's part? That seemed unlikely.
Charlie shrugged to himself and left the robe hanging by the door. It wasn't as though he had anything left to hide from Yvette and besides, he got a bit of a thrill from walking around with no clothes on. He took a breath and went through the door.
Yvette was waiting for him on the other side, along with Lexy, Erin, and David. Yvette was back in her tight black jeans, knee-high boots, and body-hugging cami. David wore similarly tight black jeans, black boots, and a black tank-top that showed off his trim, muscular arms and shoulders. Lexy lounged on the bed, wearing nothing but black bikini-style panties, bare feet, and a tiny white t-shirt that stopped well above her belly-button. From the way her impressive tits jiggled everytime she moved, it was obvious she wasn't wearing a bra underneath. Her long, wavy brown hair was pulled back in a simple ponytail, leaving her soft, elegant neck exposed. She looked Charlie in the eye and smirked as she ran her tongue over her top lip; Charlie realized he'd been staring and looked quickly away.
Erin, for her part, was wearing four padded leather cuffs, exactly like Charlie's. She was also wearing a robe similar to the one that had been hanging in Charlie's changeroom.
He suddenly felt even more naked.
"Oh, um..." he stammered ... "I guess I should..."
"Stay right there, Charlie," Yvette commanded, then, more gently, "thank you for joining us."
"Oh, um, yes mistress," Charlie managed to reply. "Hello."
He took a quick look around the room. The dramatic red-and-black color scheme, cabinets, and rubbery flooring were all still in place and the queen-sized bed with its cozy pile of pillows still dominated one side of the room.
But there were some new features, as well. For one thing, there was a cushioned, wooden-armed chair near the foot of the bed, with a small stool sitting next to it. Charlie noticed there were shiny metal rings bolted on to the arms and legs of the chair, right where someone's wrists and ankles would be.
A few feet away from the chair was some kind of padded bench or railing standing freely in the middle of the floor and seemingly bolted down where a panel of flooring had been removed. Attached to the floor on one side of the bench were two short lengths of metal chain.
Charlie's thoughts were interrupted by Yvette's most stern, take-charge voice.
"Today is all about discipline," she announced. "It was clear to me that this was lacking during our last session."
She paused.
"Yes, mistress," Charlie and Erin replied in unison after a brief moment. Yvette frowned.
"So we are going to work on instilling some of that missing discipline in the two of you. After your performance at the Cattail you should be grateful that Lexy and David agreed to help today -- I suppose Charlie and Erin's apology was sufficient, yes?"
"Yes, mistress," David and Lexy replied immediately, David's impassive expression contrasting with Lexy's wild and mischievous grin.
"Though David did have to help a little after Charlie left poor Lexy a little high and dry."
Lexy smirked at this, her tongue poking out the side of her mouth.
"I didn't mind, mistress," said David.
"No, I'm sure not," Yvette said. She slowly made her way over to where David was standing. She patted his cheek twice, then gently slapped it. "But that's not the point, is it?"
David's face betrayed the faintest glimmer of a smile.
"No, mistress," he said.
Yvette turned back to face Erin and Charlie. She took a long look at Erin and then let out a short sigh.
"David, would you please finish setting up the bench?" Yvette said.
"Yes, Mistress," David replied and strode over to the cabinets and began rummaging through its contents.
"Lexy, would you please get Charlie situated?
"Yes, Mistress," Lexy said and slid off the bed. She sauntered over to Charlie, making direct eye contact with him the whole time and putting an exaggerated sway in her nearly-naked hips. The swaying caused her tits to bounce with each step and Charlie had a hard time deciding where to look.
"Come along," Lexy said as she took Charlie's arm and led him to the chair, where he obediently sat down. Lexy smiled at him and knelt down in front of him, her head tantalizingly close to his bare and stiffening cock, then secured the cuffs around his ankles to the loops at the base of the chair. She stood up and immediately sat herself down in his lap, causing him to grunt. She fastened the cuffs at his wrists to the chair as well, then stood up and looked down at him, grinning.
"All set, mistress," Lexy said.
"Thank you, Lexy."
Lexy skipped back to where the other two women were standing. Yvette turned to face Erin, who had been watching the scene with her hands folded awkwardly in front of her. She stared down at Erin who returned her gaze with a meek expression.
"Now Erin," Yvette said. "I believe you had instructions waiting for you when you arrived in the changeroom, did you not?"
"Yes, mistress," Erin immediately replied.
"And what were those instructions?"
