"Mum! Suzy won't let me come in her mouth!"

Mum, without lifting her head from her book, lazily replied, "Suzy, let your brother come in your mouth."

"And tell her to swallow it."

Another lazy reply, "Suzy, swallow your brother's cum."

My eighteen-year-old sister struggled against my hand holding her head down and spit my cock out. I grunted in frustration, lifting my ass off the seat to try to stick my cock back in her mouth. She had one hand tightly wrapped around the base of my seven-inch cock and her other hand on her pussy. A string of spit ran from my cock to her mouth.

"But, Mum, you know I hate swallowing cum!" she whined.

Mum, a little more attentive now in the passenger's seat, turned around and lightly reprimanded the disobedient daughter. "Then you shouldn't have started sucking your brother's cock in the first place. I don't want any cum on the upholstery, so swallow it."

Exasperated, she turned back around and said to one in particular, "Honestly, I've never met a girl who loves cock so much but hates guys coming in her mouth. She loves it on her face, on her tits, on her pussy, in her pussy, in her asshole. Everywhere but in her mouth."

Over in the driver's seat, Dad gave a slight chuckle.

Mum's lewd rant was all the encouragement I needed. I grabbed Suzy's hair and forced her mouth back down onto my cock. She was evidently resigned to her fate and didn't resist. To make up for lost time, and get back at her for whining, I started fucking her mouth a little faster and deeper than before. She started eagerly bobbing up and down faster than my thrusts, disrupting my rhythm. I stopped fucking her mouth and let go of her hair and let her do all the work. I ran my hand up under her t-shirt and cupped one of her big firm tits. She groaned in pleasure and started rubbing her pussy faster.

My sixteen-year-old sister Becky had lifted up her skirt and was playing with her young pussy with one hand and sucking the fingers on her other while watching her older sister sucking my cock. She loved the idea of sucking cock but Mum said she was too young to start. She volunteered for a solution. "Can he come in my mouth?"

Mum vetoed that right away. "He's not coming in your mouth, young lady. Not till you’re eighteen."

"But, Mum! He's come in my mouth plenty of times. Why can't he do it this time? You know I love swallowing sperm."

"I know you do, sweetheart, but this is different. I let him jerk off in your mouth whenever your sister and I are out and there's no pussy at home and none of the neighborhood sluts are available. Now he has your sister's mouth to fuck and it's not fair to ask him to jerk off."

Becky pouted in disappointment but quickly went back to sucking her fingers and playing with her pussy. The first time I jerked off in Becky's mouth was last week when Mum and Dad went to the "Club" for the first time and Suzy was out sucking off the neighborhood and I had complained about being left out to hang with no one to fuck. Mum's solution was to let me jerk off in Becky's mouth.

Mum had called Becky into the room and told her to take off her clothes and get on her knees and open her mouth. Becky was all excited because she thought she was finally going to be allowed to suck her first cock. When Mum told her what was going to happen, Becky started pouting and whining. Mum had eased the poor girl's disappointment by telling her she could play with my balls while I jerked off.

It was exciting to jerk off in my little sister's mouth while Mum watched. It was definitely a different kind of kinky. Mum showed Becky how to play with my balls without hurting me, where to rub around the balls sac for maximum pleasure, how to stroke and caress my thighs.

Becky took my load like a seasoned whore. She shot one hand from my balls to her pussy as soon as my first wad of cum hit her tongue and she was making herself orgasm by the time the last wad landed on her nose. She lay back on the floor, spread her legs and lifted her knees, and started finger fucking her young pussy with one hand and scooping up the cum that was on her face into her mouth with the other, swallowing it between her gasps and moans. Mum and I watched in amazement as the little cum-slut unabashedly masturbated in front of us. We looked at each other and burst out laughing.

Mum knelt down and sucked the last few drops of cum out of my cock then turned and watched Becky finger-fuck herself. The little slut was groaning and moaning and sucking her fingers, trying to get every last taste of cum.

Mum crawled between her legs, gently caressed Becky's thighs and softly asked her, "Honey, do you want Mummy to help you come?"

Becky, normally reluctant to engage in her Mum and sister's diddling and pussy-licking, was so horny she barely hesitated before moaning a quick "yes".

It only took a few seconds of Mum's expert fingering to get the little slut off. Becky planted her feet on the floor, raised her ass up and gyrated her hips wildly. After coming she settled back down on the floor with her legs still spread wide and continued moaning softly. She had missed a big drop of cum that had landed on her chest and Mum licked it up.

Becky lifted her head to watch and protested softly, "That's my sperm."

Mum, now aware of what a cum-loving slut she had for a daughter, moved up to Becky's mouth and told her to open. Having watched enough porn Becky immediately knew what her mother was going to do and opened her mouth. Mum let the cum drip into Becky's mouth and Becky took it and swirled it around her mouth before swallowing it.

Ever since then I jerk off in Becky's mouth at least three times whenever Mum and Dad go to the "Club", whether or not a willing pussy is around.

But back to the mouth around my cock. I love fucking Suzy's mouth and did not want to get cut off, especially not on this road trip where pussy and blowjobs would be few and far between. Suzy cut me off completely before when I came in her mouth. No pussy, mouth, ass, not even a handjob, but she eventually let me fuck her after a week or so. Dad and I have an unspoken agreement that when I am cut off we would take it out on Mum's ass. Literally. Mum loves taking it up the ass but after a week of getting her ass pounded four, five, six times a day, any whore would need a break.

Suzy loves sucking cock. She gives Dad and me a "good morning" blowjob every day but Dad's the only one who can come in her mouth without repercussions and the only guy's cum she'll swallow. Every guy in the neighborhood who's made the mistake of coming in her mouth has been cut off. I had to stay on the slut's good side for this trip.

"Mum? How about if Suzy jerks me off in Becky's mouth?"

With the prospect of being able to swallow a load of cum, Becky started moaning louder. Her hand started moving faster. Mum lifted her head and thought for a moment. Suzy was lost in her own lust and didn't hear my generous offer.

Mum finally spoke. "No. To get all of your cum in her mouth without spilling any, she'll need to wrap her mouth around your cock and she's too young to suck cock."

Becky groaned in disappointment but kept up her pace.

"How about if I shoot in Suzy's mouth and she swaps it with Becky?"

That pushed Becky over the edge and she started coming. We all knew Becky loved swallowing, but until now we hadn't realized the prospect of swapping cum with another girl could turn her on so much!

Mum turned and watched Becky coming. After Becky was done, Mum said, "Becky, do you want to swap your brother's cum with your sister?"

Stupid question. By the way, Becky had orgasmed, it was obvious she would.

"Oh, fuck, yeah", Becky said weakly.

"Okay. Suzy, did you hear that?" Mum asked.

"Humph mmhph."

"What?"

"I think she said yes, Mum," I said.

"You don't have to swallow your brother's cum, Suzy, just take the load in your mouth and give it to your little sister."

"Humph mmhph." Suzy took her hand off her pussy and gave a quick thumbs up and the hand went right back to her pussy. Soon she was coming and too drained to keep up the pace with her mouth. I pulled her head off my cock, pulled her up into a sitting position, straddled her thighs, and rammed my cock back into her mouth.

She put her hands on my stomach to try to reduce the full force of my thrusts but I was too horny to be slowed down. I heard Becky moaning again and turned to look at her. She was playing with her pussy again. I noticed Mum had turned to watch. She had reached across to Dad's lap and was rubbing his crotch. Dad was shifting in his seat, moving one arm around his crotch, obviously trying to pull his cock out.

Mum said, "Becky, stop playing with your pussy and play with your brother's balls."

I turned back around and watched Suzy's lips as I rammed my cock in and out of her mouth.

I felt Becky's hands caress my ass and slide under my thighs and her fingers started fondling my balls. I groaned in pleasure and thrust my cock deeper into Suzy's mouth. She gagged but kept sucking. I heard a seatbelt unbuckle and the rewind mechanism whiz. I turned around and saw Mum drop her head into Dad's lap. The minivan swerved a little.

"Shit, Dad", I thought. "Don't crash until I come in Suzy's mouth!"

My balls tightened and soon I was shooting in Suzy's mouth. I had pulled back a little so it wouldn't go straight down her throat. Not because I didn't want to get cut off by inadvertently having my sister swallow my cum, but because I really wanted to watch my sisters play with it. My spasms subsided and I slowly pulled my cock out. Suzy kept her lips tightly wrapped around my cock until it was all the way out.

I moved off of Suzy's legs and she quickly sat up. Not because she was eager to swap my cum with my little sister, I realized, but because she didn't want my cum running down her throat. Becky crawled up between Suzy's legs, leaned back on her knees and opened her mouth and stuck out her tongue. She was so eager! My cock started getting hard again just watching her. She ran her hands up her big sister's side and grabbed her tits.

Suzy pulled her hair back with one hand and grabbed Becky's jaw with the other and leaned forward and slowly opened her mouth but kept her head back so the cum wouldn't run out of her mouth just yet.

She's teasing her, I thought. She hates oral creampies but she's got a mouthful of cum and she's teasing her little sister with it!

Becky opened her mouth wider and slowly raised up until her tongue was touching Suzy's lower lip.

"Not all at once!" Mum called from the front.

I turned and looked at her. She had raised her head off of

Dad's lap and was watching the action in the back. One arm was still over Dad's lap rapidly jerking up and down.

"Make her beg for it!"

I looked at Mum in surprise. She had a mischievous grin on her face. She moved her free hand to Dad's crotch but didn't move it. Was she going to catch Dad's load in her hand?

Suzy closed her mouth and moved the cum around so she could talk without spilling any. "Beg for it, you little slut!"

At first, I thought Becky would get angry for being forced to beg for her treat but it seemed to turn her on! I knew from first-hand experience she loved being called a slut. Every time I jerked off in her mouth I would call her a slut over and over and it worked her up into a frenzy. But having to beg for it turned her on even more.

She let go of one of her big sister's tits and started rapidly fingering herself. "Please!" she pleaded. "Can I have his sperm?"

"What are you going to do with it?"

"I'm going to swallow it."

"What will you do for it?"

"I…but…I want to swallow it."

"I know what you want to do with it, you little slut. But what will you do for me if I give you our brother's cum? Will you lick my pussy?"

Becky only hesitated a moment before replying, "Yes. Anything you want. Just give me the sperm."

"Will you let me finger fuck your asshole while you lick my pussy?"

Becky was about to say yes when the logistics of that confused her. "How can she finger fuck my asshole if I'm licking her pussy?" she thought to herself.

Suzy grew impatient and said loudly, "Well?"

"Yes, yes, anything you want. Just give me the sperm!"

"Will you lick Mum's pussy, too?"

"Yes, I'll lick Mum’s pussy, too."

Satisfied she had degraded her little sister enough, Suzy slowly leaned forward and opened her mouth and stuck out her tongue. The cum slowly started dripping out. Becky positioned herself to catch it all. My cock was fully hard again. I grabbed it and slowly started jerking off. Dad started grunting and Mum turned her full attention to him. I heard her 'ooh' and ‘ahh' as Dad shot his load. Hopefully into Mum's hand, I thought.

Suzy dripped all of my cum into Becky's mouth then leaned down and stuck her tongue in her mouth and swirled her tongue around. Becky returned the gesture, swirling her cum-covered tongue around Suzy's. Suzy sucked some cum back into her mouth then dripped it back into Becky's.

Becky moaned and fingered herself faster. Suzy crept one hand down

Becky's body and started rubbing the little slut's clit. She pulled her tongue out and started kissing and licking Becky on her cheek and neck. Becky had all my cum in her mouth but hadn't swallowed it yet.

I think she was waiting to come so she could swallow and come at the same time. Her thin little hips started rocking back and forth. She closed her mouth and started moaning louder. She leaned back and rested on her elbows and spread her legs wider so she could thrust her hips more, letting her big sister do all the work on her pussy. Suzy slid off the seat and got down on her knees between Becky's lewdly spread legs. With her other hand, she started finger-fucking Becky's pussy. Suddenly, Becky swallowed my cum, opened her mouth, and started screaming in ecstasy. She came and came and came.

I've never seen anybody come that hard and that long, let alone a sixteen-year-old girl! She finished coming and went limp, falling onto her back, her legs flopping flat onto the carpet, still spread wide. She was gasping for breath and smiling at the same time. She licked her lips, trying to find more cum to taste. Suzy has running her hands all over her body, her thighs and her chest, occasionally sticking a finger in her pussy, helping the girl enjoy the afterglow.

"Becky?" Mum softly called from the front, holding up her hand with a big load of cum in it. "Would you like to swap cum with Mummy?"