Janie bounced into her twin brothers room as he packed his clothes.  Plopping down on the bed she smiled at him threw a couple of socks at him to get his attention. He threw them back without looking up.

“What the fuck does a girl have to do to get your attention?” Janie asked.

Jamie kept packing his clothes and without looking at his sister said, “You have to be naked around here. Are you packed already?

The twins had always been close and very competitive. They weren’t shy around each other. They would fight over anything just to be a winner. They even wrestled from time to time. She knew his tickle spots, and he knew hers. 

“I finished an hour ago,” Janie teased, “What the fuck is taking you so long?”

“I just got started,” Jamie replied, “And since your not naked, get the fuck out, so I can finish,”

Janie pulled her tee shirt up, revealing her small tits with a wink and asked, “There brother. Can I stay now?”

Jamie looked at his seventeen-year-old sisters' tits and shook his head. “You fucking slut,” he said with a laugh. “I’ve seen your tits before, show me the good stuff.”

His sister laughed and said, “Show me yours and I’ll show you mine. I dare ya.”

He couldn’t pass up a dare and she knew it. Neither of them could. They were just too competitive. He started to push his basketball shorts down. She could see his pubic hair.

“I hope you guys are done packing,” their mom called out from the bottom of the stairs. “We are leaving in half an hour.”

Jamie pulled his shorts back up, then turned and started packing again. Janie grinned at him and watched him pack.

“Do you still have a crush on Missy?” Janie asked.

Jamie looked up at her and retorted, “What the fuck, I don’t have a crush on Missy.”

Janie leaned in close and whispered, “I saw you go in the boathouse with her last summer.”

Jamie looked surprised. He didn’t know anyone knew about that. His sister just kept staring at him with an accusatory expression.

“That’s right, I saw you,” she grinned, “Just what were you doing in there.”

Jamie didn’t know how much his sister had actually seen. His cousin, a Missy, had taken her top off and let him play with her tits as she gave him his first hand job. He remembered Missy’s little tits and huge puffy nipples. He also remembered cumming all over himself. But he wasn’t about to let Janie win.

“We fucked like bunnies,” Jamie said as he grabbed his crotch. “And that’s what I’m going to do to you if you don’t get out of here.”

Jamie chased her from the room as they laughed. Mom appeared at the top of the stairs as they ran through the hall.

“That’s enough you two,” she said as she noticed Jamie’s hand. “We are leaving in ten minutes. Jamie, stop chasing your sister around like that.”

“Yes ma’am,” Jamie said as he went back to packing.

Later, in the car, Jamie was getting bored with his video game so he turned his phone off and looked over at his sister. She was napping on the seat next to him. Her ass was pointed at him and her head on the armrest of the door.

Jamie couldn't help but steal a peek at his sister's ass. She was wearing those little right form-fitting terry shorts. They were really short and pulled tightly into her crack. Never really looking at his sister in this manner, he noticed how nice she looked. Her ass was right and firm. 

Bored, Jamie poked his sister’s ass to wake her. She stretched and yawned. Pushing his hand from her ass she gave him a look of annoyance. But she sat up and shook herself awake.

”What the fuck?” Janie asked. "I was sleeping."

”I'm bored, ” Jamie said. ”Wake up and keep me company.”

She looked at him and asked, ”What do you want to do?”

”I don't know, ” Jamie replied. ”What do you want to do?”

Thinking for a minute, she got a naughty grin on her face. She turned and whispered, ”You still haven't shown me your thing, and I dared you.

Jamie looked to his mom and dad in the front seat. Neither seemed to be paying attention to the twins. He looked back at his sister and shook his head. Pointing to his parents for an excuse.

Janie frowned at him and said, "You're just chicken, now I won't show you mine.”

Jamie didn't like being called chicken. He looked at his sister, then at his mom. He made his mind up. He wasn't a chicken. Alarming his sister he called to their mother.

”Mom,” Jamie asked, "Can I sit in the back seat? Janie is taking all the room.”

Janis turned and looked at her children. ”I guess so,” she replied and turned back around.

Janie looked at him as if to say you chicken.

Jamie climbed over the seat and settled into the third row. He laid flat on his back and pushed his shorts to his knees. She wasn't going to back him down. 

He slapped the back of her seat and whispered, ”You want to see it, turn around.”

Janie slowly poked her head over the seat looking down at her brother. She shook her head and said, "That's your underwear. I wanted to see your dick.”

Jamie knew she would react that way. He looked her in the eye and pushed his boxers down as well. His flaccid pecker drooped between his legs. Janie's eyes bugged out.

Realizing his sister's surprise, he reached between his legs and grabbed his cock. He shook it at her as she grinned. 

Janie couldn't take her eyes off her brother's cock as he shook it back and forth.  ”Wow,” was all she could say as she watched him.

Jamie was watching his sister’s face as he shook his dick at her, just a foot or so away. He realized a little late that he was becoming hard. He didn't mean to. It just happened. He stopped what he was doing and started to reach for his boxers.

Janie stopped him and said, “Wait, I want to see it.”

Jamie wasn’t shy if his sister wanted to see his hard dick it was ok with him. It was truly hard now as he watched her eyes.  He wrapped his fingers around it and squeezed it, exaggerating the head. Janie grinned as she saw a drop of clear liquid appear on the tip.

Jamie felt his shaft throbbing as he boldly started to stroke it for her. The pre-cum dripped from his cock head onto his belly. It hung in a strand. He continued to slowly stroke his cock as his sister watched.

Janie tentatively reached for his cock but stopped short. “Can I touch it?” she asked.

Jamie moved his hand and said, “I guess so if you want to."

She touched the tip with her index finger, dragging the flowing precum down his shaft. Jamie’s heart raced as his sister wrapped her fingers around his shaft. 

She was stroking him slowly, her fingers feeling his hardness. She felt his heart beating in his cock. Licking her lips, she continued her slow ministrations. Jamie was nearing the point of no return.

“Sis, uhm, you better stop or,” he stammered.

She gave him a naughty grin and stroked him a bit faster. His cum boiled in his loins. Janie watched her brother take a deep breath and close his eyes. 

One long thick rope of white sticky cum leaped from Jamie’s dick. Another then more. He had masturbated before but it never felt this good. 

Janie stroked his cock slowly as his cum jetted from his cock. His shirt was coated in the love juice. She gripped him firmly as his orgasm wracked his young body. His cum ran down his cock onto her fingers. 

His apex waned and he opened his eyes. His sister still held onto his fading dick. He watched her cummy fingers stroked him up and down. Finally, she released his member, bringing her fingers to her mouth. He watched her lick his cum from her hand.

“Fuck Sis, that felt good,” he breathed, “I can’t believe you did that.”

She smiled as she continued cleaning her brother's cum from her fingers.  She stuck one finger all the way inside her mouth and sucked it clean. “Well you did the dare, it’s the least I could do,” she said as she watched his cock shrink. “Your dick is nice, it’s fat.”

“What are you kids doing back there?” Janis called from the front seat.

“Jamie is letting me play with his thing,” Janie answered.

“What the hell did you say?” Janis screamed from her seat.

“He’s letting me play his game,” Janie corrected.

“Oh,” their mother said, “I thought you said, uh, never mind."

Jamie pulled his cum stained shirt over his head and balled it up behind the seat. “Pass me another shirt from my bag Sis,” he asked.

“Pit stop ahead,” their dad called, “If you need the bathroom, you better go now. Two hundred miles till we stop again.” 

Janie tossed her brother a clean shirt and watched him pull his shorts back on. She was thinking about how good his thick cock would feel in her young pussy.

“Ok, it’s your turn, Sis,” Jamie said, “You have to show me yours.”

“I don’t have one of those,” she replied with a giggle.

Jamie frowned and said, ”You know what I mean.”

”My brother the pervert,” Janie said.

”You just stroked me off and ate my cum and you call me a pervert,” Jamie protested.

Janie licked her finger again with a naughty grin and asked, ”Why do I have to show you my pussy?”

Jamie grinned and as the car turned into the parking lot answered, ”Because I dare you.”

The sun was setting as the twins got out of the SUV and headed to the bathrooms.