Part 1
Sarah slammed the car door shut and ran to the house. She couldn't believe she was arriving at her father's house naked again but as she ran up the stairs and burst through the front door she felt a momentary sense of relief in knowing that Jill was still sitting in her car and couldn't be recording her latest humiliation. Her younger step-sister, however, was smiling her usual smug smile. Not only did she have her teacher's panties to play with later, she knew exactly what Tony had been up to when he should have been at school.
Her brother sat in his room, his eyes riveted to the latest adventure of his older step-sister. He had watched her run to the house, her small breasts large enough to wobble as she ran, enticing enough to make his cock stiffen as he watched. The small camera he had fitted to the outside security one was working perfectly and he had an excellent view of Sarah's nude body as she ran towards their house. Connected to his laptop wirelessly, he now had another video to ensure his older sister did just what he and Jill told her to do.
That morning he had waited until he was sure everyone was out before he began fitting the miniature cameras he and Jill had bought online, along with the ones he had ordered on his own that she knew nothing about. They were now all connected to his laptop, ready to provide him with a lifetime's supply of free porn and maybe even a new source of revenue if he decided to share his work with others at school.
He had fitted two of his tiny cameras in the light fitting between his and Sarah's door, one facing in each direction. As she arrived at the top of the stairs and began to run down the corridor, he watched as she raced towards the apparent sanctuary of her bedroom. As she approached the first camera, Tony got a great view of her gorgeous breasts and bald pussy but it was when she passed under the light and the second camera took over the filming that he got the shot he wanted. He was already in love with his sister's bottom and he felt his hard cock twitch in his jeans as he stared in wonder at her cheeks bouncing as she ran to her room.
Just as Sarah reached the security of her bedroom, so Jill burst through the door of her brother's room.
"Well, is it working?" she breathlessly asked her twin brother.
"See for yourself," answered her smiling twin as he leaned back to allow his sister to see their older step-sister close the bedroom behind her and lock it. Only when the door was locked did Sarah's breathing begin to slow down and the memory of her striptease in her own classroom returned. Her cheeks burned red as the humiliation flooded over her and she could feel the tell-tale tingle between her legs once again.
Feeling dirty and aroused in equal measure, she headed straight for her en-suite bathroom and, once again, locked the door behind her. Jill and Tony smiled to themselves as they both knew how to open all the locks in their father's house and they also knew that there was to be no hiding from the hidden eye of their cameras for poor Sarah.
"You didn't point one of them at her toilet, did you?" Jill asked mischievously, knowing full well the depths of her brother's depravity.
"Of course not. What do you take me for?" her indignant brother replied, trying hard to hide the blush on his face. There was a camera pointed at their step-sister's shower, however, and their attention was dragged back to the screen as they watched Sarah walk towards it and turn it on. After waiting a few moments for the water to heat up, she climbed in and the twins stared at the small screen; their naked sister innocently picked up her bottle of shower gel and poured some into her left hand, before rubbing it all over her body, her right hand joining her left as they caressed ever inch of her smooth skin. Tony could feel his cock stretching within the ever tighter confines of his jeans while Jill squirmed beside him, wondering if he would notice she was just as turned on as he was.
Their eyes never left the laptop as the warm water ran all over the sexy body of their step-sister, washing all the suds off her clean skin, all the way down her long legs. As she finished soaping her body, she reached for the shampoo and, pouring some into her left hand again, she tilted her head back and began to wash her long, dark hair. This made her small breasts stand out and Jill and Tony were astonished all over again at how sexy small tits could be.
As Sarah turned to let the water wash the shampoo from her hair, she faced the unseen camera and began to play with those very breasts. Tony thought she must have been washing herself again but Jill noticed how hard her step-sister's nipples had become and realised there was something else going on here. As the unsuspecting teacher began tweaking first one nipple then the other, running her wet finger around them, the grinning twins watched in delight as they saw her slide her right hand down her body towards her equally wet pussy. Her pussy, of course, was wet inside and out.
They watched intently as a single finger rubbed up and down her lips. Her mouth opened and they suspected she was moaning in pleasure, even if they couldn't hear her. As she continued to rub at the lips with one hand while playing with her breasts with another, Tony thought he was going to cum without even touching himself but the best was yet to come.
Jill desperately wanted to do exactly what her older sister was doing as they watched Sarah part her swollen pussy lips with one hand and stared as she brought her other hand down from her breasts. They were almost sure they could hear her squeals of pleasure as she inserted just one finger into her pussy and began to easily slide it in and out. Tony was just as anxious to touch his cock, torn between watching and wanting to join in. When Sarah slid a second finger into her pussy and began to masturbate even faster, both twins let out a moan of desire.
Sarah didn't last long and when they watched her face contort in ecstasy, they knew she was cumming. She had no idea anyone could see her as her legs almost gave way, forcing her to lean back against the shower wall, still plunging the fingers of one hand in and out while her other hand concentrated on her swollen clit, teasing it throughout her powerful orgasm before it finally stopped and she slumped to the floor.
Both Jill and Tony were desperate for some time on their own so, when Sarah eventually lifted herself to her feet and turned the tap off, Jill made her excuses and practically ran to her bedroom. Tony now had to decide if he would rerun what he had just watched or switch to the secret camera even Jill didn't know he had planted in her room.
Part 2
He switched momentarily to the camera in his twin sister's bedroom, the one he had placed in the smoke alarm directly above her bed. He was rewarded when Jill bounced on to the bed and, in one movement, had lifted her skirt and plunged two fingers into her obviously very wet pussy. He finally was free to open his jeans and release his cock but, as he did so, he noticed his sister wasn't content to masturbate to the memory of what they had both just witnessed. She had produced a pair of white lacy panties which she was holding to her face and licking.