Chapter 7: Mistress-Sister

"What do you think you're doing, Slave-Brother?" I asked, slapping at his hands as he tried to stuff his cock and balls into his trousers. "I'll tell you when we're finished."

"Oh shit ... uh ... Mistress..." Jim stared helplessly at his penis and then at me, begging silently with his soft brown eyes.

Knock knock...

"Jim?" we could hear Cheryl's voice through the door, soft and slightly muffled.

We were in his office at the radio station, me sitting on an old imitation loveseat against the wall, and my brother standing in front of me with his large cock stiff and dripping precum just in front of my face. I'd been whipping it with a short leather strap earlier and it still bore the marks of my expert attentions. His balls were hanging out as well, nice and slightly plump after I'd noosed them with the strap, using it as a leash.

He was my slave now, my little submissive, just as our parents were and I'd been incredibly excited by our little scene. I still was, and so was Jim despite his sudden panic at the thought of being discovered by his wife, Cheryl. But his cock wasn't going soft either, he had his own fantasies regarding his wife and being found out in his infidelity. He reminded me quite a lot of our mother.

"Stand back ... Move..." I pushed against his firm stomach with my palm so Jim would give me some room to stand.

"What are we going to do ... We ... We can't..." my brother licked is lips.

"Be quiet!" I slapped his cock hard enough to get his attention and he winced, staring into my face as I stood up.

"Mistress?" He was like a little boy caught doing something he shouldn't have and his eyes were pleading with me to get him out of it.

"Leave your cock and balls alone," I told him. "And assume your position. Here, facing the sofa. I'll talk to Cheryl."

I was walking towards the door, slapping the leather strap against my thigh. I didn't bother to look behind me; my brother would be doing what I told him. He didn't have a choice. We were caught and if Cheryl was going to accept any explanation, any plausible excuse for why we'd be locked together in his office, she'd have to hear it from me first.

I didn't know what I was going to tell my sister-in-law. We didn't know each other very well and she was two months pregnant with their first child, which had seemingly made her a little emotional, a little insecure about herself. The fact that she was already suspicious of Jim cheating on her hadn't helped the woman either and we'd had a little talk the night before. I'd given her a shoulder to cry on then.

And so now we'd have another talk, but this one would be very different.

"Hi Cheryl," I smiled at her as I opened the door wide, demonstrating that there was nothing to hide.

"Uh, hello ... Susan," she blinked and couldn't help but look me up and down, it was only natural.

I was a little flushed with pleasure and I was reasonably sure that my cunt reeked of sexual excitement. I was hot from dominating my brother, from putting him willingly on his knees and making him my new slave. My breasts felt swollen in the leather top I wore, straining at the laces of the corset-like enclosure. My black mini-skirt had ridden down, exposing my flat tummy and the top of my black thong as it curved over and around my hips. I looked like I'd just had a pretty good time and Cheryl couldn't help but stare.

She looked nice herself, if a little less exciting in her appearance. Cheryl wore a pleated skirt that fell to her knees, a pleasant shade of yellow, almost golden, and a simple button down blouse above that, baby blue and made of cotton like her skirt. The outfit showed off her body nicely, which was more athletic than voluptuous. The woman wasn't tall, but she had nice breasts, not overly large, and a narrow waist and hips. Cheryl was almost boyish, but no one would ever mistake her for anything but a woman.

Cheryl was very attractive, and so young too. She was just twenty years old and looked barely that, more like she'd just stepped out of a high school yearbook. But that may have been the air of innocence she carried with her. The way she could smile with just the corners of her soft red lips turning up, like it was a secret smile meant only for the person she was giving it to. And her eyes were hazel colored, like a doe's and flecked with gold. Her eyes were incredibly beautiful to me and with her face made up nicely, and her long auburn hair pulled back into a ponytail, I couldn't help but want her.

"Come on in." I stood aside for the young woman and I could see Pauline behind Cheryl, sitting at her desk and staring at me. Pauline had to be hopelessly confused now and I wondered how much she'd heard through that locked door.

"Where's Jim?" Cheryl asked, stepping past me and she'd see him in a second.

"Go ahead and take the afternoon off," I told Pauline, giving her a little smile. "Jim won't be needing you today. Spend some time with Tyler."

"Uh ... Are you sure?" Pauline rubbed her lips with her fingers.

"Jim?" we could hear Cheryl's voice filled with surprise. "What are you doing?"

"Yeah," I giggled and rolled my eyes a little. "We need to sort out some family business."

"I..." Pauline started moving slowly, " ... I'm sorry about ... You know..."

And she was sorry, I could tell. Whatever the reason she'd been fucking my brother, Pauline hadn't intended to hurt anyone by it. I'd judged her much too harshly earlier, remembering the stuck-up little girl I'd known in high school. She'd plainly grown up to be something else, someone real, and it seemed very unlikely Pauline had seduced my brother ... But he did have a wonderful cock. I would understand if she had.

I put Pauline out of my mind and closed the door, locking it behind me and Cheryl was close to Jim now, staring at him and trying to understand why he'd be on his knees. He had his back to her, so she hadn't seen the best part of it yet. Not until a moment later and I smiled as her eyes got big.

"Jim?" Cheryl gasped, but she got no answer from her husband. He had his eyes closed and his face was crimson.

He'd assumed the proper position too, with his back straight and his shoulders and elbows back, hands on his head. His cock was hard as steel, angry red and aching for release. Beneath it hung his balls, nice and big, hanging out of his trousers like they were begging for attention. Slave-Brother was being a very good subbie just then and it pleased me a great deal. He was quiet and blushing and trying his best to ignore Cheryl's demands for an explanation.

"Susan, what's going on?" Cheryl stared at me and her expression was changing, like she couldn't decide how she should feel.

"How much do you love your husband, Cheryl?" I asked her, sitting down on the loveseat a few feet in front of Jim. I tapped the sofa gently. "Come here, sit down with me."

"I love him," Cheryl said simply and she narrowed her eyes, but did as I asked, sitting down beside me and alternating her looks between me and my newest slave.

"But how much?" I smiled at her, turning slightly so I could face her.

We could forget about Slave-Brother for the moment, he wasn't going to do anything unless I told him to. He was terrified with guilt and excitement. He'd been caught finally and I think he was exactly like Slave-Mommy in that he was dying to have his secrets known and be punished for them. He'd inherited more than just her brown eyes and hair.

"I..." Cheryl shrugged. "More than anything. Why? What's going on?"

"Enough to punish him?" I smiled at the sudden look she gave me. "Do you love him enough to hurt your husband, Cheryl?"

"Hurt ... Why would I..." she swallowed hard.

"Would you punish his cock if it had been in another woman?"

I was teasing her a little, but this was the path as I saw it and I had a feeling about her, an idea that had occurred to me just as I'd opened the door for her.

"Would you make him sorry that he'd cheated on you, Cheryl? Sorry enough that you could forgive him?" I continued gently, my voice soft and coaxing her to answer me faithfully.

"You..." She stared at me and there was fire in those hazel eyes, the gold inside burning hot for a second.

"No," I shook my head. "We didn't do anything like that. I was just teaching him."

"You didn't fuck him?" She stared into my eyes and she wasn't afraid of it the way so many people are.

"Slave-Brother, did you fuck me?" I asked Jim without turning my head.

"N-No, Mistress-Sister," he answered properly, although his voice cracked slightly.

"Mistress ... Sister ... Slave ... Brother..." Cheryl turned her head to look at him for a moment. "What does that mean?"

"He's my slave now, my lover ... But not in that way, not like you think," I told her, and that was a slight stretch because I knew I'd be fucking my brother soon enough.

"Your lover? ... That's ... Incest..." She was confused, but only a little, Cheryl was smart, she was quick. Another woman might have gotten stuck there for a moment or two, silly as that seems. People are often slow to grasp the obvious when it makes them uncomfortable.

"Does it bother you?" I asked.

"He's my husband so, yeah..." she gave me a hard look. "It bothers me."

"I could teach you," I offered and that was my ace, the only one I had. Cheryl would either accept it or this was going to be a long difficult afternoon for all of us.

"Teach me?" Cheryl didn't get that, not yet.

"Slave-Brother, tell your wife a secret," I commanded him.

"Mistress, I don't, uh..." he was obviously reluctant, despite his desire.

"What secret?" Cheryl stared at me.

"Oh, he has a lot of them," I sighed, returning her gaze. "But we can make them go away," I promised her. "I can show you how."

I stood up, and without a word or a warning I brought the leather strap down hard on my brother's unflagging cock.

SLAP!!

"Ahhh ... Mistress!" he jerked hard, almost losing his balance, but he didn't take his hands from his head, he didn't try to protect himself.

"What are you doing?" Cheryl's voice was shrill. "My God!"

"Tell her a secret, Slave-Brother," I told him again, ignoring Cheryl for the moment.

"Y-Yes, Mistress ... I ... I cheated on..."

"Not me, slave ... Tell your wife!" I grabbed his jaw roughly and pointed his head towards Cheryl, who sat stunned with her mouth open, staring at us.

"Cheryl..." he swallowed hard and he was burning with humiliation, trembling with fear, and his cock was dripping precum as it had been for the last hour.

"You'll address her as Mistress Cheryl from now on!"

SLAP!!

"Ohhhh Yesss ... Mistress ... Mistress Cheryl..." he groaned, but he'd had the look in his eyes even so. The devotion was obvious beneath the pain.

My brother's cock would have welts now, those two strokes had been hard ones, intended to punish him and demonstrate for Jim's wife exactly how willing he was to be punished.

" ... I cheated on you ... I fucked another woman ... I-I'm sorry, Mistress..."

Cheryl didn't say anything, she just sat there taking it in, working it all out. Her husband was being whipped painfully, being made to confess his adultery, and he was addressing her as Mistress now. I was Jim's Mistress-Sister, Cheryl would be his Mistress-Wife and he would belong to her completely. I'd let him go for her, knowing the woman would need me to help her, to train her how to be the Domme that I sensed she was inside.

"Punish him," I urged Cheryl, holding the leather strap out for her in my open hand. "Make him demonstrate his love for you before you forgive him."

"I don't know if I can forgive him," Cheryl stared at my brother and I really hoped she wasn't lost to us.

That was the risk, as it had to be. She'd been weak and insecure since her pregnancy, hardly a dominant personality at all, but it was inside her. That was the source of her conflict, in my opinion, the reason for her unhappiness. She needed to be assertive and strong, to assume her proper role as the Top to her husband's bottom, but she didn't have the experience. She didn't have the strength by herself, not with my brother who had always been the stronger ego in every relationship he'd ever had.

My brother had been spoiled by girls who'd loved him and he'd come to expect the attention, the devotion. He'd had girlfriends since he was barely fifteen and none of them had broken up with him, it had always been Jim saying goodbye. No girl had ever slapped him, or said no to him; not a one had refused him. He was too handsome, too charming and comfortable to be with. Everyone loved Jim and he knew it, so why would Cheryl be any different in his mind?

But he wanted her to be different, that was the beauty of it. When I'd had him call his wife Mistress, all of my brother's pain had gone away, just for an instant. He'd said her name carefully, lovingly, offering himself completely, with the words dripping from his tongue. He was a man who wanted a woman to serve, but only if she could prove herself worthy. If she couldn't, he'd fuck her and leave her, or in Cheryl's case he'd just fuck around behind her back.

He wanted to be caught. He wanted to see her reaction, to test Cheryl that way. If she was like all the other girls she'd forgive him and love him and let him do it all over again, so that they'd be miserable and apart their entire married lives. It was the trap my parents had fallen into, my father not dominant at all and my mother testing him with her infidelity. He hadn't even noticed, or more likely he hadn't wanted to.

That would be Cheryl in a few years, if she didn't take the strap from my hand now.

"Punish him," I urged the woman. "Decide afterwards if he deserves you or not."

Cheryl closed her eyes, breathing deep and I couldn't read her thoughts.

"Beg her, slave," I told my brother. "If you love her, prove it now or lose her forever."

It sounded melodramatic, but it was the truth and he knew it.

"Mistress..." my brother's voice quailed, " ... Punish me, please ... I was wrong, I love you. I don't deserve you, but..." he cleared his throat as his voice had gone soft, " ... Please, Mistress Cheryl ... Punish my cock ... My balls ... Anything..."

Cheryl was watching him, the corners of her pretty mouth turned down and she was touching her tummy, where their child slept blissfully ignorant of their little drama.

"Give me that," Cheryl stood up and took the leather strap from my hands. "Like this?" she asked, doubling it over as I'd done and I nodded.

"He's your slave now," I urged her softly. "Take him."

I'd have to watch closely because anger is the very last emotion you want when Topping a slave. It leads to nothing good and it's a betrayal of trust. I was reluctant for that reason, but there was no other choice. It had to be done this way and I knew Cheryl loved him, I had faith in that. She would hurt my brother, I was certain, but I wouldn't let it go too far. I was staying very close. The physical pain would be worth it for him anyway, if it saved them both from the emotional torture they might find otherwise.

"I hate you," Cheryl breathed and she brought the leather strap down hard on my brother's exposed penis with a sharp snapping sound.

SLAP!!

My brother's body spasmed with the shock of that cruel leather biting into his turgid flesh. He gasped loudly and his hands came off his head, but only an inch and then he regained control.

"You want to fuck around on me?" she questioned him softly, speaking to herself as much as him.

SLAP!!

"Argghh ... Misssss..." my brother hissed loudly, gritting his teeth against the pain.

"You bastard ... I love you!"

SLAP!!

"I-I'm ... Sorry..." Our slave was panting, his eyes wet and his cock was moving around, bobbing up and down from the hard stinging slaps it was getting.

"Sorry?" Cheryl snorted derisively. "What does that mean?"

SLAP!!

"I love you!" my brother gasped.

The blows were not so hard as I feared, but very soon the skin was going to break, I was sure of it. He had welts now, rising hot and white, small blisters on his cock and there were parts of it that looked raw and sore. He'd take more, my brother was strong and his limits went beyond mine, at least for the moment, but that too was a problem with doing a scene while you were stressed. He'd take as much as Cheryl could give him and thank her for it, oblivious to the physical danger he might be in.

SLAP!!

"Mistressss..." Jim moaned and his shoulders sagged, his arms wilting.

"That's enough..." I whispered, putting my hand on Cheryl's shoulder.

She was hot and breathless and she nodded, licking her lips and staring down at her husband.

"What do you say after being punished by your Mistress-Wife, slave?" I asked Jim sternly.

I got down so that I could examine his penis. The strap of my purse wasn't very stiff at all, and it was smooth so that there was little risk of abrasions or cuts, but he had been whipped hard with it and what concerned me most was the underside of his cock, where the urethra lays close to the skin. The rest of the shaft was tough and could handle a lot more abuse than we'd given it, but I liked to be cautious.

"M-Mistress ... Thank you for punishing me." Jim could barely catch his breath and he was close to exhaustion. His body was tense, every muscle knotted and his shirt was soaked through with perspiration.

"Fuck you." Cheryl stared at him and then she reached down, grabbing my brother by his short brown hair, pulling his face up to look at her.