"What's that?" Sienna asked, spotting the metal case in her older brother's hand. She sat up straighter. Her online lectures were done for the day and she was thankful for a distraction.
"None of your business squirt," Callum replied. He set the case down on the table and walked over to the coffee machine. Switching it on before turning and resting his ass on the kitchen side, facing his sister.
"Don't call me that!" she whined, then immediately regretted her tone. She always tried desperately to not let him get to her. She took a deep breath. "Seriously though, what is it?" She ran her fingers through her long blonde hair, well, almost blonde, her dark roots starting to show through. She knew she needed to sort that out.
"Something from work we've been working on," Callum said. "I wanted to try it out over the weekend." He waited for his coffee, glad it was Friday at last. It had been a tough week and he needed to unwind. He still had a bit of work to finish, nothing too taxing, a bit of testing, and then he could do whatever he wanted.
"I was hoping for your help actually," he added. He watched his sister look up and stare at him suspiciously.
"With what?" she asked.
"I've been working on a lie detector," he said, his eyes flicking to the case. "It's supposed to be unbeatable. I'm pretty confident in it, but it needs more testing."
Sienna thought for a second, her brain addled by her lectures. She decided it would be a laugh.
"I'll do it, if you go on it after, and I ask you questions," Sienna said, losing herself slightly in his bright green eyes.
Callum thought hard, he knew how good the machine was. He didn't see any harm though, and it was a good test. "Okay," he agreed.
"Yes!" Sienna said, excited. She jumped up. "I'll just get dressed." She hurried out the room and Callum watched her go, his eyes falling to her slender legs beneath the white baggy t-shirt she was wearing. It was long and looked like she had nothing on her bottom half. Maybe she didn't, he thought. He shook his head and turned to finish making his coffee.
"She's grown up," he muttered. Shame trickling through him. He shook his head again. She might be 18 now, but shes still my sister, he thought.
Callum was sitting at the table when Sienna came back in. It took every ounce of his self control not to look over her body.He knew what she was wearing, having checked her out plenty of times in it.
Sienna smiled inside as she watched the inner struggle of her brother. She knew the black leggings she wore and the blue crop top made him uncomfortable. It showed plenty of skin and highlighted her perfect slender body and firm round breasts. She knew it was wrong, but there was something about the glances he gave her that made her feel good. Wrong, but good. There was no harm in a few fantasies, she thought.
"I'll just get a drink," she said and headed to the cupboard, unintentionally giving her brother a great view. Callum took in her body again. The tight leggings highlighting her long slender legs and perfect round ass. They were low on her hips and her ribs tightened her skin as she reached for a glass. Her thin, toned waist visible beneath her crop top.
Sienna poured herself some juice and went over to the table. She plonked herself down into the chair opposite her brother.
"Where do we start?" she asked. She was glad their parents were out. It was always nice to spend time with her brother. There wasn't enough of him lately, what with her studying and his work. She missed him.
They had always got on. The occasional brother and sister argument, but generally they enjoyed each other's company. And he's quite easy on the eye, Sienna thought. His short, perfectly styled blonde hair. His naturally lighter. His handsome features and an athletic physique. He was just over 6 feet, so had quite a few inches on her. Which she liked in her men.
She watched him stand and put the metal case on the table. He opened it and took out a small black box, pressing a button that made a blue light come on. He looked good in his work stuff. Smart trousers and a blue shirt.
Callum moved and stood above his sister and brushed her hair behind her ear, noticing the shiver that ran down her spine. He attached a small node to her temple. His eyes drifted to her cleavage, her firm breasts pushed together in the V of her top
"It's not very big," Sienna said, looking up. Callum nearly jumped and pulled his eyes away. Looking into hers. Recovering nicely.
"Size isn't everything," Callum said, smiling. He winked.
"Ew gross," Sienna said. "Number one in the top ten things you never want your brother to say. And the wink just made me sick a bit in my mouth."
Callum laughed. "Now sit still whilst I calibrate it." He started pressing buttons and turning dials.
"Is it a yes and no jobby?" Sienna asked, starting to feel nervous. She wondered why she agreed to this. There were certain secrets in her head that maybe she didn't want to reveal to her brother. No scratch that, definitely didn't want to reveal.
"No. It can read whole sentences," said Callum. "That's what makes this new one so special." He pressed a button and it hummed gently to life.
"Oh that's good," Sienna said, nervously. The computer made a sound like you get when you answer a question wrong on a game show. EEH EEH.
"Your first lie," Callum said, grinning. "Starting to feel nervous, Squirt?"
"No!" she said. The same noise. Callum laughed. "Oh for fucks sake." She had definitely made a mistake here.
"Okay. Let's start," Callum said. "Some obvious questions first to just check if it's working. Is your name Beryl?"
"No. My name isn't Beryl," she said. The computer went ping, the truth.
"Are you a pygmy goat?" Callum said, grinning.
"Yes I am," Sienna laughed. He knew she liked pygmy goats. EEH EEH. "Phew. That would have been a shock.
"Am I your brother?" Callum asked.
"Unfortunately you are," Sienna joked. Trying not to use yes. She wanted to see how good this thing really was. PING.
"Good," Callum said. He leant back in his chair, thinking.
"Don't be mean," Sienna said. "Remember I'm helping you."
Callum smiled. "Wouldn't dream of it," he said. He leaned forward. "Do you like my art work?"
Sienna laughed. "Dickhead," she said. "Yes I do." The machine pinged. The truth. "After some praise are you."
Callum smiled. "Just checking you weren't just being nice," he said. He liked to sketch and sometimes paint in his spare time. Sierra always encouraged him, he just wanted to make sure she wasn't being kind when she said they were good. "Thank you."
"Have you ever stolen anything?" he said, a quick change to catch her off guard.
Sienna stuttered. Blushed. She decided it was best to tell the truth. "When I was 8 I stuck a pink pencil into my coat pocket," she said. "It was in the old local shop. I've felt guilty ever since." PIMG.
Callum laughed. "You rebel," he said. "I promise not to report you."
"Hey. I'm a good girl," Sienna said. "That moment was a blip in my honest and flawless personality." She smiled sweetly and Callum admired her pretty features.
"I'm sure there's some darkness in there somewhere," Callum said. "You can't be all sweetness and light."
Sienna dramatically placed her hand over her heart, almost cupping her firm round breasts. Callum couldn't help but look,and looked back up quickly.
"How could you say such a thing?" Sienna replied, just as dramatically as her pose.
Callum thought hard. There must be something on her he thought. Too many inappropriate questions flooding his mind.
"Do you have a boyfriend?" he asked. This was the least inappropriate he could think of.
"Bit personal," she muttered. "No I don't." The machine pinged.
Callum felt a strange sense of relief at the truthful answer. He then realised an error.
"Girlfriend?" he asked. His sister's eyes narrowed.
"No," she said. The machine pinged. "I am not romantically involved with anyone." PING. If he asked a few weeks ago it might have been a different noise from the lie detector. Her recent relationship, with a guy, had ended a bit messily. The usual, he wanted more, but she wasn't ready for that kind of commitment from him. She was disappointed because the sex had been good. She remembered it fondly and felt a stir in her lower abdomen. It had been a while since then.
"Your love of Justin Bieber scare them off?" Callum said, laughing.
"Fuck you," Sienna said. She gave him the finger. That was years ago but she knew he loved teasing her.
"You wish," Callum said. An automatic response.
"Yeah right," Sienna started, forgetting she had the lie detector on for a second. "I wouldn't want to go anywhere near you." EEH EEH. The computer highlighted the lie instantly. Sienna blushed. Callum gave a sly smile. Interesting, he thought.
He knew it was wrong but he couldn't help embarrassing his sister, time to step things up. "How often do you masturbate?" he said.
Sienna's mouth opened in shock. "Never!" she said, not thinking again. Her mouth going into defensive mode. The lie tone. "Well, I might do it occasionally." EEH EEH. Callum laughed.
"Tell the truth now sis," Callum said. A big grin on his face.
"I'm not answering that," Sienna said, defiantly.
"Remember you get your own back after," Callum said. Now feeling slightly worried about pushing his sister too much. It would be worth it though, he thought.
Sienna considered this, and thought too that it would be worth it. How bad could his questions get? And she was sure her self pleasuring was pretty normal. They had always been quite close too, being honest with him wasn't hard.
"Most days," she said quietly. The machine pinged.
"What was that sis?" Callum asked, he had heard her perfectly, but was enjoying making her squirm.
"I play with myself nearly everyday," she shouted, the machine pinged again.
"That's quite a lot," Callum laughed.
"Not as much as you," Sienna said. "I hear you all the time, your bed banging the wall." Callum's smile dropped off his face. A ping.
"Well you shouldn't be listening," he said sulkily.
"Well I don't listen on purpose," Sienna said, the computer spotted the lie. She flushed red. Callum grinned.
"So you listen to me wanking then?" he asked. He felt his cock hardening in his trousers, he knew he shouldn't whilst talking about this stuff with his sister, but he couldn't help it.
"It's hard to ignore," she replied, looking down at the table. PING. The truth. "Can we change the subject?" She too was starting to feel aroused by this conversation.
"Not yet," Callum said.
