Daniel’s bedroom door blasted open, interrupting him in his work. Daniel looked up to see who was barging into his room. Of course, it was his younger sister. She was pompously standing in the doorframe, confidence beaming in her brown eyes. She brushed her wavy, dirty blonde hair behind her shoulder as she walked up to his desk.

“What are you doing here, Lizzie?” Daniel asked, irritation clear in his voice. He was still in the middle of revising for his upcoming exams.

“Mom and dad just left on their weekend trip,” she proudly announced. She was wearing light clothing during the ongoing heat. Her white tank top was tucked into her denim shorts, showing off a lot of her pearly white skin. She bent over to get right into Daniel’s face, sitting behind his desk. Her neck was already showing a tinge of red, even though it had barely been hot for a day or two.

“So?” Daniel replied curtly. “What about it?” he asked as he turned his chair back to face his textbooks. Daniel had to spit through another three chapters that day, so he was not in the mood for her antics. Of course, he knew their parents had just left the house, so why did she have to come over to state the obvious? ‘Maybe she’s just bored,’ he guessed. She was eighteen, a year younger than him, and had just finished her final exams. She was now just hanging around, waiting for the results. She could most likely go to her first choice university if they were positive.

Lizzie wasn’t daunted at all by Daniel’s dismissive attitude. “I was just thinking,” she mused cheerfully, while she forcefully turned him back around in his chair to face her. “That this would be the perfect time to give you another ‘challenge’, wouldn’t it?”

Daniel’s eyes widened and his heart skipped a beat. He looked straight through the gleeful expression on his sister’s face, aware of the hidden meaning behind her words he had long been oblivious for. He felt a jolt in his crotch, after which he put his hands to try to comfort it. “Does it have to be right now?” he tried, his composure melting away at a rapid rate.

“Oh?” Lizzie replied surprised. “Don’t you even want to try anymore?” she asked him, disappointment in her voice. “So you don’t mind me sending a few pictures to mom right now?” Lizzie backed up to get her phone out of her back pocket, already navigating to her gallery.

“No! No, I mean please don’t do that!” Daniel scrambled to stop her. Lizzie expectantly looked up from her phone, although her thumb kept scrolling through her photos. “I-I just tried to say that I was pretty busy,” Daniel tried to explain. “But if you want to do it right now, that’s also fine.” Sweat was dripping along his back, which was not coming from the heat in his room.

“I hoped you’d agree,” Lizzie said happily as she put her phone back in her pocket. For a brief moment, Daniel wondered that he had dodged a bullet, but it seemed like it had still grazed him. “You obviously don’t want them to know what a pervert you are,” Lizzie started. Daniel’s heart sank as the humiliation started coming down on him. “Sneaking pictures of your sister when she’s wearing her cute bikini on the beach,” she continued, running her hands over her naked thighs. “And furiously masturbating to that sight for weeks,” she kept teasing.

As Daniel tried to avoid his sister’s gaze, he noticed someone standing behind his sister. It was a bit dark in the hallway, but he instantly recognized her. It was Maya, one of Lizzie’s friends with whom she often hung out. ‘No…’ Daniel wondered to himself. ‘She wouldn’t…’ His sister was practically shouting that her brother jacked off to pictures of her, while her best friend was standing right behind her. Panic welled up in Daniel’s chest. Maya must have heard everything, and Lizzie’s words couldn’t be spun in any other way.

His sister noticed the anxious look in Daniel’s eyes, as his voice was stuck in his throat. She followed his gaze, which was fixated on the girl behind her. “Oh god, you don’t have to worry about Maya, Danny,” she giggled. Daniel looked at her confused. On what earth didn’t he have to worry that not only his sister but now also someone else knew about this?

“Yeah, this is nothing new for me,” Maya said as she walked up to Lizzie, putting her hand on Lizzie’s shoulder. She reached out with her other hand to show Daniel something on her phone. His mouth fell open while she scrolled through her chat with his sister. Not only were there chat messages from months ago indicating that Maya definitely knew what was going on, but there were also pictures. Dozens of them. Of him.

Daniel knew that his sister had been taking pictures of him. It was hard not to notice her pulling out her phone during one of her ‘challenges’. He had just naively assumed that she kept those for herself, probably for even more leverage over him. He had never dreamed that she would directly send them to her best friend. The photos were bad enough, but the accompanying conversations made him look like an even bigger fool.

Seeing that Daniel now believed her, Maya put her phone away. “I was really curious how Lizzie had trained her big brother,” Maya said. “You saw that she kept me up-to-date pretty well, although maybe a bit too well,” she remarked, giving Lizzie a look. His sister just sheepishly smiled in response. Shaking her head, Maya continued. “Let’s just say that I really wanted to see it for myself. But I have to say that I’m not that impressed yet,” she voiced to Lizzie.

“Well, he’s still Daniel,” his sister laughed at the opinion. “He can be a huge blockhead,” she criticized her brother, “but that’s just how I like him.” This surprised Daniel. Maybe this explained her unyielding attitude when he tried to brush her off. “Let me show you how to flip his switch, though,” she moved on.

‘Oh no,’ Daniel wondered to himself again. ‘She cannot, not right in front of-‘ His train of wondered was stopped when Lizzie put her hands on her chest. She bent down even further, almost pressing them up against his face. She put her fingers under her cute, firm breasts, pressing them against each other.

“Do you wanna get hard for Lizzie?” she asked in a sugary voice. “Is today the day that Danny is going to win my challenge?” As if someone had pulled the emergency brake, all trains of wondered had stopped in Daniel’s head. He stared at his sister’s breasts, looking at the outline of her bra, barely showing through her shirt. The only reason he got back to his senses was because of the sharp pain in his crotch. He let out a yelp and put both of his hands on his lap.

“Oops,” Lizzie said, quickly standing back up and pulling her hands from her chest.

“What happened?” Maya asked curiously, as it was now her turn to get up close.

“Ehm, I kinda forgot he was still locked up.”

Maya looked back at her friend with a raised eyebrow. “Don’t you do this, like, all the time?” she asked, perplexed.

“Yeah, but I guess I was nervous or something. You wanted to see Danny so suddenly, so I wasn’t really prepared,” Lizzie tried to explain herself.

“I have been asking for weeks,” Maya poked right through it. “You just wanted to show off, didn’t you?”

“Okay, okay, you’re right. Come on, Danny, let’s get to my room,” Lizzie evaded losing face. Daniel got up from his chair, while Lizzie had already stormed out of the room. He heard Maya giggle. He saw that she found the whole ordeal endlessly amusing. Now that he took a good look at her, he noticed that the few days of sun had already colored her skin olive brown, in shrill contrast to his sister. Maya was wearing her black hair in a ponytail like usual. She was wearing a crop top and airy shorts, presenting more of her skin.

“Aren’t you going after her?” Maya caught him gawking at her. “Or are you too busy?” She turned to face him. She was a few inches taller than his sister, almost matching him in height. She winked at him and mimicked what his sister had done just now. She put her hands under her breasts, hidden behind the tight top she was wearing. She pushed them together just like Lizzie had done. Her fingers dug into her boobs, which were a lot larger than his sister’s. She released her grip, making her tits bounce back to their original position.

Daniel hadn’t seen anything that sexy for months. He had to manually close his jaw, which had hung open from surprise. This made Maya giggle again. “Let’s get to your sister, she’s waiting for us,” she urged Daniel as if nothing happened.

Lizzie was already sitting on her bed when Daniel and Maya entered the room. She tapped the spot next to her. “Come here Danny, let’s get you out of your cage.” Daniel swallowed. He carefully sat next to his sister. Maya got a chair from behind Lizzie’s desk and sat in front of the bed, as a spectator. Lizzie put her hand on Daniel’s thigh, continuing as if no one else was in the room. “Pants off, Danny,” Lizzie commanded.

Daniel obediently followed her instructions. He was pretty used to being naked in front of his sister, but today it was pretty nerve-wracking. The piercing gaze of Maya was almost unbearable. While Lizzie was removing her necklace, Daniel was sweating bullets. He was now in full display in front of his sister’s friend. It wouldn’t have been that bad if he were not wearing this chastity cage.

“Oh my god, you really fit him in there,” Maya gasped when she saw it. “I thought it was pretty big,” she asked his sister. Lizzie was still fiddling around with her necklace. She opened up the small heart that was hanging onto it, unveiling a small key that was hidden inside.

“It was,” Lizzie casually responded. “But after some practice, it fit like a glove,” she proclaimed.

“So it actually shrunk?” Maya reacted in disbelief.

“Mhmm…” Lizzie confirmed. “But he is still as big as ever when he can get hard,” Lizzie said, but this time in Daniel’s direction. By now, he was bright red. Them talking about his package while he was presenting it right in front of them was just too much. And Lizzie was not stopping. “This wouldn’t have been necessary if mister hadn’t been disobedient,” she said, reminding him of what he had done. Earlier on, she had caught him masturbating. She had forbidden him from doing that, so this was his punishment. That was when he learned that his sister bore a grudge because that instance had been months ago.

“Is he always wearing that?” Maya kept asking eagerly.

“Yup,” Lizzie said proudly. “Even when he’s sleeping. I can’t be too sure, can I?” she gave Daniel a look, indicating that this was his own fault.

“That’s so hot,” Maya gasped. “Your little sister has you completely under her control, hasn’t she?” she giggled. Daniel didn’t know what to do, so he simply nodded. He couldn’t deny it.

“Good boy,” Lizzie whispered in his ear. Immediately, his breath got ragged. “Let’s get you out of your tiny little cage,” she said sweetly.

His cage was not more than a few centimeters in length. It was see-through, clearly showing how it was straining against its container. Lizzie opened the tiny padlock, which kept the cage together. She carefully removed the cage, freeing his small penis.

“It looks even more pathetic when he’s out of his cage,” Maya remarked. This opinion stung in Daniel’s heart. “Can he even get hard anymore?” she asked Lizzie.

“Of course he can,” Lizzie responded encouragingly. Meanwhile, she kept running her fingers along Daniel’s thigh. “He just needs a little help. Look over here, Danny,” she urged him. Daniel’s eyes immediately darted to his sister’s chest, knowing what was about to come.

Lizzie pulled her shirt out of her shorts and up towards her chest. Daniel could now see her slim, white waist. “Are you ready?” Lizzie asked him, grinning. Daniel nodded intensely. He had completely forgotten that someone else was with them in the room by now.

His sister finally revealed her breasts. She was wearing a light-blue bikini top, showing off lots of her cute breasts. They were only a small handful, but Daniel could almost feel how firm they were by merely looking. Lizzie would more often show her breasts to him in her bra, but today was special. She was wearing the same bikini top as in the initial picture which got him in all this mess.

“Get hard for Lizzie, Danny,” his sister told him sweetly. Not a moment later, his unwavering and minuscule penis started rising rapidly. Maya’s eyes widened, not expecting this sort of result. “Go on, you can do it,” Lizzie kept cheering him on. “Get hard for me, Danny. You’re almost there.”

“Good boy, Danny,” Lizzie said with satisfaction. She squeezed her breasts together, so much that Daniel almost wondered her nipples would begin showing. This marked the end of the ride, as she hid her bikini top under her shirt again. It took Daniel a few breaths to be able to tear his eyes away from her now-hidden breasts.

“Look, I told you he could still get big!” Lizzie proclaimed smugly. She wasn’t lying, as Daniel’s cock was now standing straight upwards, jumping up and down from excitement.

“I have to give it to you,” Maya admitted. “He’s got a pretty nice cock.” She reached out with her hand, but Lizzie caught it.

“Please no touching, Maya. We’re just getting to his challenge.” For the first time, Lizzie looked completely serious.

“Alright, alright, I’m sorry,” Maya hastily retreated. “Just forgot about that for a bit, you don’t have to get angry.”

“I’m not angry,” Lizzie replied with a smile. “I’m just making sure the game stays fair, right Danny?”

“After what you have shown me just now?” Daniel looked at her incredulously.

Lizzie wanted to counter but shut her mouth again. “Alright, you got a point. But I didn’t touch it, though. And you have to admit, you loved looking at my boobs, right?” They both looked at his cock, still rock hard. Nobody could deny he loved his sister’s tits.

“Well, Maya, what kind of challenge do we want to do today?” Lizzie inquired.

Maya had known this question was coming and had already prepared her answer. “Three strokes,” she said without a second wondered. “I want him to cum in three strokes,” she said with bated breath. “You said he could, right? I really wanna see that.”

“Ehm, yeah he can, but-” Lizzie carefully answered, but Maya interrupted her.

“Then that will be his challenge for today,” Maya concluded. “He has to cum within three strokes, or he can’t have an orgasm.”

Daniel was getting increasingly worried. He wasn’t sure if he would be able to cum in just three strokes. He knew if he lost the challenge, it would take ages for him to be able to get another shot. “What I was trying to say was that he had an orgasm like a week ago,” Lizzie tried to defend him. “Usually, I keep him waiting for longer if I want to try something like this.” Daniel silently rooted for his sister, hoping Maya would be a bit more lenient.

“So?” Maya asked quizzically. “I’m sure he’ll do just fine.” She wasn’t having any of it and didn’t relax her rules in the slightest. Daniel could only hope his sister would come up with some rebuttal.

“Fine,” Lizzie sighed. Daniel looked disheartened at his sister. “But he’ll need a bit of help,” she added. She gave her brother a reassuring smile. “Do you mind if I’m the one jerking him off?” she asked Maya.

Daniel was stunned. His sister had barely even touched his cock, let alone given him a handjob. “Whatever, if he cums in three strokes, I’m fine with it,” Maya agreed offhandedly. “Is he ready?” she asked impatiently.

“Almost.” Even though his cock was rock hard, Lizzie didn’t yet begin the challenge. She got up from the bed, standing right in front of her big brother. “I think he needs a bit more help before we start.” Lizzie pulled up her shirt completely now, revealing her chest once again. She didn’t stop there, though. She turned around and bent over, her tight butt right in front of Daniel. She slowly pulled down her shorts, swaying her ass all the way. She was now only wearing a bikini. Lizzie ran her fingers underneath the matching bikini bottom, readjusting the fabric and snapping it back in place. She looked back over her shoulder. “Did you miss your little sister’s bikini, Danny?”

“Oh fuck yes,” Daniel could only breathe out. Summer had just started, so he had waited months for her to begin wearing her bikini again.

The beaming smile on Lizzie’s lips told him that this was the right reaction. She turned around and walked up to him. She gently pushed him back, until Daniel was sitting against the back of her bed, while she crawled after him. “Spread those legs a bit for me,” she whispered to him. As he did, she went to sit between them, putting her legs on top of his. She rested her feet on either side of him.

With Lizzie’s legs spread like this, only a thin layer of fabric was hiding her pussy from Daniel’s view. “God, you’re so hot,” Daniel murmured. He wasn’t sure if he had ever been this excited.

Lizzie was in turn looking at his cock. Veins were running along the shaft, all the while it was throbbing dangerously. Lizzie smiled at this. “That’s more like it,” she said triumphantly.

Right next to them, Maya flopped down on the bed. Lizzie looked at her annoyed. “What?” Maya asked the siblings. “I couldn’t see anything from up there.”

Lizzie rolled her eyes with a smirk. “Let’s just ignore her,” she whispered in her brother’s ear. He couldn’t help laughing at that.

“I can hear you guys, you know?” Maya commented. “It’s about time you two start.”

“Yeah, yeah, don’t worry,” Lizzie waved her away. His sister focused her attention completely on him now. “You heard Maya,” she said softly. “Are you going to cum in three strokes for me?”

“Yes Lizzie,” Daniel whispered back.

“Are you going to shoot out loads of cum for Lizzie?”

“Yeah…” Daniel breathed.

“Good boy.” His cock jumped firmly at the compliment. “Let’s start.”

Daniel anxiously watched his sister’s hand reach toward his throbbing cock. An electric shock ran through his body the moment her fingers touched his shaft. She had by now wrapped her hand completely around his shaft.

“Make sure to take a good look at my boobies, alright?” Lizzie urged him. Daniel nodded shakingly. He focused his attention on her breasts while feeling her touch his cock for the first time.

Without any more words, Lizzie’s hand started moving upwards along his shaft. Another electric shock hit him the moment her fingers touched the tip. She closed her fingers around the tip, making sure to get every bit of stimulation before she stroked downwards. With one stroke, she had brought him toward the edge.

“One,” Lizzie counted. “Are you going to cum for me?” She whispered in his ear again. Not expecting an answer, her hand started moving up again. When she rubbed along his tip, Daniel started moaning audibly. “Good boy, you’re doing great!” Lizzie cheered him on.

Daniel was now standing on the utmost edge of his impending orgasm. He was so close, but he was still worried. He had just one more stroke to go. Would he make it?

“Two,” Lizzie whispered. “Don’t worry, Danny. We’re going to do it,” she comforted him. She got even closer to his ear. “Cum for me, Danny. Spurty spurt for Lizzie.”

Something in his mind clicked. All his worries faded away, as he felt himself going over the edge just by her words. “I’m cumming, Lizzie!” Daniel moaned.

“Good boy, let it all out for me,” Lizzie grinned. Her hand moved upwards one more time along his shaft. The moment she hit the tip, Daniel’s hips buckled and the first stroke of sperm shot rapidly out of his cock. “Keep going, just like that,” Lizzie encouraged him as her fingers kept enclosing his tip slowly. Load after load kept shooting out of Daniel’s cock, enclosed in his sister’s fingers. Only when she started making her way down his shaft, it started to calm down.

The last drops were dripping down Lizzie’s hand when they heard someone cry out right next to them. The siblings both looked to their left in surprise. They were just in time to see Maya come to a shaking orgasm right next to them. One of her hands was feverishly moving in her shorts, while the other was firmly planted on her breast. She was lying on the bed with her eyes closed, her back arched and her hips lifted off the mattress.