All characters are over 18.
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Mark was slightly annoyed that he had to go into town that morning. His mother was out at work but would be back around midday. She had arranged to take him and her sister, Pat, to a shopping outlet soon after she arrived home. Mark's Aunt Pat was staying for a short time and had seduced him. Going into town that morning would intrude on precious time alone with her, but there was no avoiding it.
He had to go into the bank to arrange to transfer some money. He determined to arrive there more or less as soon as it opened so that he could get back to his aunt as quickly as possible. She was forty-eight years old. He was half way to his nineteenth birthday. And, though not quite a virgin, he found sex with her intensely exciting. He knew that in part (though not entirely) this was due to its illicit nature
She came downstairs just as he was putting on his shoes. He blushed with excitement as he remembered the previous night. He also blushed because of her sexy appearance. She was wearing a floral satin dressing robe. It reached just half way down her slender, well-toned thighs and hugged her smallish breasts. Her hair was quite short and smartly brushed, and she was wearing her glasses as usual.
She smiled.
"You off then, Mark?"
"Yes. Yes I have to go into the bank," he replied.
"Don't be too long, will you, hun?"
She smiled suggestively and to his delight she placed one hand on each flap of her robe by her thigh and drew it aside. He gazed intently as her thigh came into sight, then her puffy, shaved pussy. She left it bared just for a moment then covered herself again. She laughed at his spellbound expression.
"I presume you have your mobile with you?" she asked, and smiled approvingly when he nodded.
"That's good, Mark. Give me a ring when you're on the bus heading back home. Then I can be ready for you!"
She kissed him on the mouth and he felt her firm breasts against his chest. He headed out of the door and to the bus stop. He hoped that nobody would see his budding erection and tried hard not to think of his aunt. It was easier said than done. Images of her sitting on his lap telling him a "story" of an aunt who noticed her nephew was attracted to her came to his mind. That was how she had seduced him.
Although he tried to latch his mind onto other things he recalled their out-of-town trip and the way she had dressed as a hooker and had him book a room in a somewhat run-down hotel.
And he thought of how she had encouraged him to peep round the lounge door, supposedly unknown to her, while she read an erotic book and pleasured herself. And how he had then joined her.
His erection tightened. He looked out of the window at the passing scenes and traffic.
His business at the bank took very little time, though he had felt stupid -- his mind was wandering to his aunt and he had to be asked a couple of times for some details. The cashier smiled patiently.
He checked his watch and rushed out of the bank to the bus stop. If he was quick he should just about be able to catch the 10.14 back home. To his relief, although the bus was in sight as he drew near to the bus stop, it was stuck at the traffic lights, and he reached the bust stop just before it did. He paid his fare and found a seat. He grabbed his mobile and rang hers.
Pat was also in a distracted frame of mind. Only a few days remained of her stay with her sister, Linda. Moreover she did not know just how many more opportunities for sex with her nephew would still present themselves. Linda was keen to spend as much time with her as she could, and although she had to go into work for a few hours some days, she was trying to work as short a time each day as she could. Pat looked at her watch. She smiled. There should be time, she told herself, time to have sex with him before Linda arrived back and presented her with the need to focus, to act casual, to hide what had taken place just a little earlier.
She switched on her mobile and kept it close to hand as she awaited his call. She tried not to look at her watch again. When the phone rang it startled her a little.
"Oh hi, er... it's me."
"Hi Mark. You on the bus?"
The mere sound of her voice excited him. He recalled her plea for him to be back soon for a nice surprise.
"Yeah, I should be home in about twenty minutes." He was about to ring off but she spoke before he could.
"Hang on a moment! Mark? Are you sitting on your own? Can anyone else hear me, do you think?"
He felt a shudder of apprehension. He glanced round casually.
"Er, no... No. I don't think so."
His nerves were on edge as he wondered why she was asking.
"Last night was a lot of fun, wasn't it?" she continued.
He tried to concentrate on wording his answers as if the conversation was innocuous. He decided to try to avoid using the term "Auntie" in case it aroused suspicion.
"Yes. Yes it was. A LOT of fun," he replied. He looked a few rows ahead of him. A young mother was making faces at her toddler to keep him quiet. Across the aisle and a couple of rows ahead an elderly couple looked contentedly through the window, oblivious to him and his phone conversation.
Mark's mind shot back to the previous night and he felt the start of another erection. He had accompanied his parents and his Aunt Pat to the pub for a few drinks. It had been both a delight and a torment. It had not been easy to keep his eyes off her nor to act casually. He was desperate to avoid any hint of the dreadful and illicit relationship that he now had with his mother's sister. The fear of betraying their secret -- and the genuine shame he felt about it -- nevertheless were a big part of its appeal.
He re-checked that nobody could hear her voice down his mobile.
"Especially when we got home. That's when the fun -- the naughty, dirty fun REALLY started, isn't it Mark?" she went on.
His erection pressed harder against his trousers as he recalled the scene, though it sounded as if she was going to rehearse it all to him anyway. Although nobody seemed able to hear what his aunt was saying, it was very embarrassing and shameful to be listening to it in public.