Suggested story. Kemps!

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A pool party with four beautiful girls! Liam was one of the luckiest boys in the town. The weather was perfect, the drinks were good and the girls super sexy! He didn't know why he was invited. He wad good friend only with one of the girls and barely knew the others. It wasn't important. Liam's only objective was play the part of the cool boy and maybe impress some of the girls.
All was going well. The girls laughed at his jokes and he was the center of attentions.

Things changed when Selena, the girl who hosted the party, suggested a game. "I know what we could do. We can play tie up games!" the other girls cheered at the suggestion. Liam didn't object the idea. Since the girls were all in he didn't want to be a kill-joy.
"And who gonna be the one tied?" Indiana said in a sing song voice. All the girls giggled looking at Liam. His heart began to beat faster.
"i think we should tie up the boy!" added Natalie poking Liam's ribs.
"well girls..." Liam scratched his head.
"oh i don't wanna hear you argue! It's fair. We're four girls and one boy! It's your fate!" Dove, the girl friend of Liam, cut him off. She smiled to him and took his hands. She walked him on the grass. "now stay still!" Liam thought she looked great in her white grid bikini and orange sunglasses.

Liam looked around wondering what was going to happen. Natalie and Selena brought a wooden board while Indiana was carrying a bag full of ropes. The board wasn't too large but a little taller than Liam if you put it vertically.

Selena leaned the board against Liam's back and held it in place. Dove brought Liam's hands behind his back and on the board. "stay still. Don't move now!" she was the only one who talked. The girls seemed to be very organized.

While Dove held Liam's hands Indiana tied his wrists together. In the mean while Natalie was on her knees in front of Liam and was tying his ankles to the board. She adjusted her black bikini knowing that Liam was glancing at her boobs and smiled to him. She was the one with the  bigger breast. When she was done she crossed her arms under her chest making her breast look bigger. She didn't move from her knees and kept on smiling at the poor boy.

Liam was so mesmerized by Natalie that he didn't realize how tightly the other girls were tying him to the board.
Several loops of ropes were holding him to the board. His feet and hands out of use. He was stuck on the place.
"Liam i hope you will forgive me for this!" Dove said sarcastically.
He tried to say something but Selena gagged him shoving a napkin in his mouth. She kept his mouth closed with some loops of tape. She winked at him and kissed his cheek. She was definitely the sexier one with her red lipstick that matched the color of her fashion swim suit.

This wasn't what Liam expected from the pool party but things were still going pretty well. The gag was uncomfortable and the ropes tight but he didn't mind his state. For a boy of his age being tied by girls could be a "fun" experience.

You can imagine how aroused he was when Indiana lowered his swim trunks exposition his torbing penis to all the girls. He moaned for the excitement.

"let's get the table!" Selena exclaimed and gestured Dove and Natalie to follow her. Alone with Liam Indiana couldn't help but tease him a litte. She faced him and took off sensually the beach scarf she wearing on her waist. She moved her ass for Liam to enjoy. "should i go on?" she asked putting her thumb inside the waistband of her white bikini bottom.

"we didn't tie him for that!" Selena scolded Indiana ironically. Dove and Natalie were carrying a small metal table. It had a hole in the middle you usually use to put a beach umbrella in.

Liam was more than confused by the situation. He didn't know what to think or say. Lucky for him he was gagged! By now he understood that everything was planned before and he only let the girls do whatever they planned to do. He still hoped for some sexual experience!

He struggled in pain when Selena tied a piece of cooking twine aroud his balls. The girls placed the table vertically and leaned it on Liam's front. He found himself squeeze between the board and the table like ham in a sandwich.
One end of the twine was passed through the table hole.

Indiana and Natalie struggled to lift up the table so the hole was right above Liam's crotch. The two girls held the table in place while Selena and Dove secured Liam's at the table itself with several loops of ropes. They made the knots very tight.

Now, very carefully, the girls put the table on its legs. Liam found himself lying horizontally on the wooden board that was secured at the bottom side of the table. His body were stucked between the board and the table. His head was laying on the board as well as his feet.

Giggling in excitement the girls pulled the twine ultil Liam's balls and penis popped out from the hole. His manhood looked like an odd centerpiece. A green tablecloth was settled on the table. It covered the ropes but Liam's balls were still visible cause of the hole the girls had cut in the middle.
Selena tied the twine all the way around Liam's balls making them clearly visible.
Although the situation was still erotic, Liam began to feel a little scared. He was in an extremely vulnerable position. His balls were literally served in the table.

Hearing the girls talking apparently everything was ready for the game. In a mixture of excitement and fear Liam wondered what kind of game they gonna play. Hopefully one that involved stroking his penis.

All the girls set at the table. They made up the teams and dealed the cards. Kemps. They were going to play Kemps. Selena and Dove against Indiana and Natalie.
Liam groaned in discomfort. Why they stripped and tied him only to ignore him and play cards? He squirmed and fought against the ropes. His gag muffled all his attempts to yell at the girls who seemed to not care about his complaints.

"i'm so excited! I've never played kemps like that before" Natalie couldn't contain herself.
"it's super funny! I did it to my ex when he cheated me! To punish him" Selena poked Liam's balls.
"but our poor Liam didn't do anything wrong" Dove laughed and caressed her friend's hair.
Indiana slapped Liam's balls "but he's the only one with balls here!" she exclaimed. All the girls giggled watching the funny centerpiece bouncing under Indiana's hand.

"Ok, ok. Let's start!"
The air was filled by the sounds of the girls' hands stomping on the table to change their cards as quickly as they could.
"Kemps!" Natalie shouted out loud and slapped Liam's balls. "oooohhhmmmmm" The poor boy groaned and tensed up all hid muscles for the pain. All the girls stared at him and laughed. For a moment they didn't care about the game and just enjoyed the sight of the tortured boy.
"yhea 1-0 for us!"

The second round was as fast as the first! Liam's balls were still aching when "Kemps!" Selena punched him with all her might. Liam's balls were flattened by her first as him let out a long muffled moan.
"Stop complaining that much!" Selena reached Liam's penis and gave him a few strokes. "ahahah He's hard!" Indiana pointed out.
Liam lifted his head to see the girls who were staring back at him. "Enjoy the game?" asked sarcastically Natalie.
"no. Too much bikini girls for him to handle" Dove  squeezed her boobs between her arms emphasizing her cleavage.
"enough teasing!" Selena slapped Liam's penis and dealed the cards for another round.

Natalie looked at Indiana and lifted an eyebrow. Dove noticed that and as fast as she could she yelled "cut" and punched Liam's penis. "Kemps" almost in the same moment Indiana hit Liam's balls quite hardly.
"wait i cut. I cut first" Dove complained.
"but you didn't hit the balls. It doesn't count if you don't punch the balls. Those are the rules!"
Selena explained talking out loud to be heard among all Liam's yells of pain.

The girls argued for a bit but eventually Dove had to surrender to the rules. "Fuck" she said and slapped Liam's balls for the anger.

Liam couldn't believe what was happening to his balls. It was too easy for the girls to tie him like that. He blamed himself for being so stupid. Not knowing how to excape he decided to endure the game. After all Selena was the only one who punched full force. Natalie from time to time tickled the tip of his penis and Liam loved the sensation. He still hoped for something sexual but he didn't know that the party was just at the beginning.