Disclaimer: Everyone in this story is over 18 years of age. If you find incest in any form offensive I'd suggest you give this story a miss.
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For Liam, finding out his sister Samantha did porn didn't come as a surprise. For her eighteenth birthday her then boyfriend -- a 32-year-old photographer -- had given her a brand new set of tits, increasing her bosom to an impressive 34DD. Sam had been delighted with them, and was probably even more delighted with her parents' horror at their little girls new look. She had goaded them at every opportunity, walking around in nothing but a bikini top as soon as the sun peaked out from behind a cloud. It was only the threat of being kicked out that eventually forced Sam to calm down, although only slightly. The photographer hadn't lasted long, and only got to play with his new toys for six months before Sam dumped him to, in her own words; "have more fun." Fun certainly wasn't hard to come by for Sam - her new tits, year-round tan, long blonde hair and tight, toned body meant that every guy she met wanted to have their way with her -- and Sam absolutely loved it.
So, for Liam, when he got a text from a friend containing the URL to a website for a pornstar called Sammy Love, and the words 'isn't that ur sister?' it didn't shock him that much when he logged onto the site and was greeted by his 19-year-old little sister's smiling face and naked breasts. Truth be told, it had turned him on. He'd come to terms with the fact that he found his sister attractive the day she'd come home with her new breasts, and had often spied on her when she was in the shower of having one of her many lingerie parties with her friends. Little sister Sam - or Sammy Love -- was a hot girl who just happened to be his sister.
Confronting Sam about her secret was easy; in fact Liam revelled in it. He wasn't coy or tacit about it, instead choosing simply to greet her as Sammy Love when she arrived home one afternoon. It was the first time in his 18 years of being her sister that he saw genuine fear in Sam's eyes.
"How did you find out?" she asked, shocked, after wiping tears from her cheeks and eyes.
"I found your website. Why Sammy Love?" he had asked, with a grin on his face. Sam didn't answer.
"Are you gonna tell Mum and Dad?"
"No."
He meant it. He wasn't going to blackmail her or hold the sword of Damocles above heard, what Sam did with her life was her business and Liam knew he had no place interfering with it. That being said, for the last sixth months it hadn't stopped him from teasing his sister about her choice of 'career', and he would often ask her distasteful or unpleasant questions when she arrived home. His favourite at the moment was "did you drink much today?" which he would make sure to ask when at least one of their parents was present. They thought he was referring to Sam's partying, but if they'd have paid attention to their daughter's reaction they'd have probably realised that there was a little more to it than that.
Liam knew he would be in no place to tease Sam if she ever found out his 'little secret', however. A quick check of his internet history would expose him, which was why he'd started locking his bedroom door every time he left the room. His parents thought he was up to something, but the 'something' he was actually up to was way beyond anything they could imagine. He couldn't become a member of Sammy Love's website; that much was obvious. He doubted whether she actually had anything to do with the running of the site herself, but if someone saw his surname on the membership list then there was a chance that two and two would be put together.
God bless video streaming sites, then. Liam had built up quite a collection of Sammy's videos; all of them were catalogued in his favourites to be watched over and over again. She had never done anything that Liam would consider truly 'hardcore', mostly sticking to lesbian or standard 'boy fucks girl' stuff. There was one video of some nameless guy shooting his load all over his little sisters tits, which was a video Liam liked to cum to. He imagined that it was stream after stream of his own cum splashing down onto her breasts, and that she was looking into his eyes as she massaged the hot, milky liquid into her skin.
Inevitably, the post-wank shame hit him and he would close down all his browser windows, clean himself up and then spend half an hour feeling guilty about what he'd done. Then he'd start feeling horny again and images of Sam would fill his mind.
Aside from the easy access to images of her getting fucked, Sam's career in porn had other upsides. The fact that all her female friends now seemed to be unutterably gorgeous was the main one, they were all in porn as well, and they would all come over to the house at least once a week. Right now was one of those times, and Liam sat in the living room watching four hot women, one of them his sister, through the French doors from his living room as they sat in the garden chatting whilst wearing nothing but tiny bikinis. He knew all their names -- Sam, obviously, as well as Belinda, Carly and Lori - or, if you wanted to search for them on the internet; Cassie Hart, Violet Ray and Andi Rhodes.
His sister was the stereotypical blonde porn star. Belinda was redheaded, light skinned, small breasted and only just 5'2". Liam thought she'd get sunburnt given her light, almost porcelain skin, although much to his delight Sam had started helping her out by rubbing lotion on every visible inch of flesh. Carly was a brunette, with hair that reached halfway down her back and sometimes covered her pert 32C breasts. She was somehow ignoring the action between Sam and Belinda as she chatted away with Lori, another brunette, with slightly smaller breasts and a short, almost boyish haircut.
Liam could feel his engorged cock pressing against his boxers. He'd been hard almost from the moment he came into the lounge and saw the girls outside, giggling and frolicking in the South England sun. Now, though, he was fully erect, and knew he'd have to go and relieve himself. Luckily his parents were out and the girls didn't look like they'd be coming in any time soon, so he was able to take himself up to his room without the danger of anybody noticing his funny walk.
Liam removed his t-shirt as he entered his room - he liked to be completely naked when he masturbated so his shorts, boxers and socks soon found themselves piled on top of the discarded black shirt. The bedroom door slammed shut and Liam threw himself onto his bed, cursing the location of his house -- he couldn't watch the girls out of the window as he stroked himself, as the houses that backed onto his would have a clear view of what he was doing, should any one of his neighbours happen to pass by their windows. Closing his eyes Liam gripped his thick shaft, and the voice that had been telling him he'd forgot to lock his door was soon banished and replaced by the sound of his sister moaning and squealing in one of her videos.
Knowing the object of his desires was downstairs wearing practically nothing had sent Liam's head swimming. He struggled to maintain concentration as his right hand pumped up and down on his 7 inch dick, as he tried to visualise his sister straddling him and riding him like she'd ridden so many other men.
Liam's concentration coupled with forgetting to lock his door would come back to haunt him, though. He didn't hear Belinda and Carly enter the house, yelling to Sam and Lori they'd "be out in a second." He didn't hear them climb the stairs, as their bare feet barely made a sound on the carpeted floor. He even missed Carly whispering to her red-headed friend; "have you ever wondered what Sam's brothers' room looks like?" followed by the two girls' giggles.
Opening the door, Belinda almost did a double take as her eyes took in the fantastic site before her. She had always thought Liam was attractive, but never imagined he'd be so well endowed. She was no stranger to big cocks, but seeing one so big in her private life was unusual, to say the least. She felt Carly squeeze her head past hers to get a look, before her brunette friend dragged her back into the hallway.
"We've got to go and get Sam!" exclaimed Carly, barely able to conceal her excitement.
"Carl, no, we can't!" said Belinda, only just managing to stop herself from laughing.
