Thanks to everyone who has supported and encouraged me over the length of the series. If you enjoyed it, please let me know in the comments.
Usual disclaimer - Everyone in the story is over 18.
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It had been a life-changing few months for the family. A deadly virus, who's only treatment (treatment, not cure) was semen, had lead brother Simon and younger sister Emma into an incestuous relationship. Soon, older sister Anastasia, who had moved out of the family home months before, was helping them keep it secret, and enjoyed playing with herself while her younger siblings fucked.
Less than a week ago, a death in the family had caused the family to be separated. Peter took his daughter Emma up to Scotland for the funeral, and they soon found themselves in bed together. Meanwhile, back in the south, Anastasia helped Simon to seduce their mother, on the grounds of helping her win the tennis competition her world revolved around.
And as father and daughter drove back home, the radio announced the best and worst news possible. A cure for the virus, the very reason their world had devolved into taboo incest, had been found.
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Emma and Peter arrived home late Saturday night. Yulia and Simon were at home, still trying to find the best place to display Yulia's new trophy. Anastasia was not there. Takeaway Chinese was ordered, and they sat together in the dining room, eating and discussing the past few days. They talked about the funeral and the wake. They talked about the tennis tournament, and how close or easy each game was. They talked about everything except what was on everyone's mind. Sex.
They didn't talk about how Peter had saved a woman's life on the journey to Glasgow.
They didn't talk about how Emma had fallen into bed with her father.
They didn't talk about the second and third time they'd made love in the hotel room.
They didn't talk about how Anastasia had helped Simon seduce Yulia, their mother, and the threesome they had on their parent's bed.
They didn't talk about the quickie between mother and son in the tennis club changing room.
And they certainly didn't talk about the fact that everyone now knew the truth about Simon and Emma's secret fucking.
Finally, Peter spoke up.
"Emma, Simon, would you excuse us please. I think I need to talk to your mother about a few things. Maybe you could go to the living room and put on a movie?"
"Sure Dad," replied Emma sweetly, and left the room, with Simon close behind.
The siblings went into the living room and found a random movie to pretend to watch.
Emma started the long overdue awkward conversation.
"I...um...I slept with Dad."
Simon had already guessed by the way she hadn't come into the house shaking or a raging nympho.
"Did you enjoy it?" was all he could ask, a tinge of jealousy in his voice.
She nodded. "Yeah. He was different to you. Not better. Just different. Don't worry, I still like you."
Simon understood. His turn.
"I slept with Mum. Well... I fucked her. We didn't sleep together."
"Oh" replied Emma. This had been a surprise to her. "Did you enjoy it?" she parroted back.
"I guess" he replied. "She was different. Your pussy is tighter. She's more experienced. Different. Both good."
Simon coughed, then continued. "She knows about us. Anastasia told her."
Emma simply shrugged. "Dad knows about us too. I told him."
"So what happens now?" asked Simon.
"I don't know" replied Emma, truthfully. "I just don't know."
--
They didn't have to wait long until that question was solved. Peter and Yulia walked into the living room.
Peter did all the talking. Emma and Simon just sat on the sofa and listened.
"OK. We've talked. We've been honest about everything that has happened over the past few days and months. We know you've been having sex. Your mother knows about me sleeping with you, Emma, at the hotel room. And I've even told her about my brother and sister when we were teenagers. Your mother has told me about how you and Anastasia tricked her into intercourse. And she's told me how you both willingly had sex at the tennis club. Does anyone have anything else that needs to be spoken about?"
"Umm" spoke up Emma, very softly. "Simon had to sleep with Karen from church group when we had the sleepover. She was infected and coughing blood. We, um, had a small threesome."
Peter and Yulia nodded. "Thank you for being honest."
After a silence that showed there were no more revelations, Peter gave their parent's final verdict.
"The media says the cure is being mass-produced now, and will be distributed world-wide within a week. So until then, Emma and Yulia still need regular sex. So this...situation.. can continue, under the following rules."
He paused before continuing.
"1 - Everyone in this family is honest with each other. No more secrets between us.
2 - If you are going upstairs to have sex, you tell us.
3 - Sex stays in the bedrooms. We don't want to walk in on you in the kitchen or have the neighbours see you in the back garden.
4 - Nobody else knows. This is our family secret. If guests come over, they know nothing.
5 - When we are cured, we sit down again and decide the future, and how we interact in a post-virus world."
He stopped to see if there was any challenge, before continuing to instruct their children.