The Midnight Visitor (750 words)

Justin arrived home from university for winter break and found his mom busy preparing the house for guests. She told him Aunt Lauren and the twins were staying over Christmas. Lauren was his mom's younger sister and had twin daughters, Riley and Megan. He hadn't met them in years.

That evening when they arrived, Justin was amazed by the sight of his cousins -- he had remembered them as bratty little girls, but they were now nineteen and gorgeous. Riley was blonde and Megan was brunette, but they had the same voluptuous figures with long legs, wide hips, and large breasts. Justin's mom often complained that her sister had all the family's attractiveness genes, and it looked like her daughters had received them too.

"Wow, Justin," said Riley, while their moms were busy catching up, "You're looking hot."

They giggled as he blushed. "We thought this was going to be a boring Christmas," said Megan, "but I think we're going to have a lot of fun!"

Justin's winter break took an unexpected turn from then on. He found himself sharing a house with a pair of gorgeous young women who flirted with him constantly. He found himself tongue-tied into speechlessness every time one of them made a suggestive comment or deliberately brushed up against him. Once, when his back was turned, one of them even grabbed his butt. They giggled when he spun around in surprise, but he wasn't quick enough to see which one had done it.

His biggest surprise came on the third night of their visit. As he lay in bed he heard his bedroom door open, and someone slipped inside in the darkness. Before he had time to ask who was there, he felt someone getting into bed with him. His heart began pounding as the intruder straddled him. A pair of lips met his, and he allowed himself to be pushed back onto his pillow. He reached up to find a lithe, naked body. He knew it was a cousin's body, but he couldn't stop himself getting hard.

His visitor whispered in his ear, "Ssshh! Don't say anything. This will be our little secret!"

She pulled down his boxers and he gasped as he felt her guide his cock into her pussy. She put her hands on his shoulders and began rocking her hips back and forth. Justin gaped in astonishment as he realized he was having sex and he didn't even know who his partner was. He ran his hands up her body and fondled her breasts. He heard her moan softly as she increased the intensity of her motion and he soon began to feel his climax approaching.

"I'm going to cum," he whispered urgently, but she shushed him and carried on, and a moment later he was ejaculating inside her. She waited until he finished pumping sperm into her, and then climbed off him. In an instant she was gone, and he was lying alone in bed, sweaty and cofused.

The next day, both girls acted as if nothing had happened, and he couldn't work out which one it had been. The next night, his anonymous midnight visitor returned. He was fucking one of his cousins, and he didn't dare ask either of them in case he guessed wrong and revealed their incest. Whichever it was, she visited him every night for three whole weeks, until he returned to university.

By the time summer break came round, Justin had put the episode behind him. He didn't expect to see Aunt Lauren and the twins again for years, so he was surprised to find his mom preparing the house for them to visit again. They arrived the next day while his mom was at work.

Riley walked in first, and Justin was shocked to see her cradling a heavily pregnant belly.

"Justin, we need to talk about last Christmas," she said. His heart raced. It had been Riley who he'd been fucking.

Just as he was starting to panic that he'd fathered a child with his cousin and everyone would soon know about it, his eyes turned to Megan and widened in horror when he saw that she was pregnant too.

"We were naughty and shared you," said Megan, rubbing her belly, "and you knocked us up."

However, his biggest jolt of all came when Aunt Lauren followed them inside and he saw that her belly was just as swollen with child as those of her daughters.

"All three of us," she added.