Disclaimer: Anal, rimming, cum eating, voyeurism, dirty talk. The dad does not get involved sexually.
Thank you kenjisato for the editing.
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Zack was fifteen when his dad left him and his mom. Since then, he worked every summer at the supermarket. He also did some odd jobs here and there as a handyman. His mother, Claire, worked as a cashier in a hardware store. Fortunately, she was full-time. They scraped that plus the pension for three years to send Zack to college to get a business degree.
Just a month before he went to college, they left their small apartment to live with a man her mother met two months earlier. Zack thought it was a bit quick, but her mother vouched for her new boyfriend. The few times Zack met him, he did seem like a decent guy. As long as his mother was happy.
From what his mother told him, Oliver was recently divorced with a good job as a heavy-duty mechanic that takes him all over the place. They met using a dating app and hit it off immediately. His mother was ready to date again now that Zack will be off for college soon. He also had a daughter, Khloe. His mother had met her as much as Oliver met him, so Claire didn't have much to say about her. She only knew that she was starting her senior year in high school as Zack was starting college.
Even after they moved in together, Zack didn't interact with her much. Since he worked during the day and Khloe was gone, or in her bedroom most nights, they seldom talked. Which is a shame he thought since she was pretty.
The new house was a welcome change for Zack and his mom. Three bedrooms and a bathroom upstairs, one bathroom downstairs. His mom could, at last, grow a vegetable garden. Oliver insisted that Zack had to finish college before they helped him pay the mortgage. His mom refused, but she couldn't convince Oliver otherwise.
The day he was officially moving out to college, Oliver helped him while his mom had red eyes all day. Her mom hugged him in front of his dorm, until people started commenting.
"C'mon, mom, you have to let me go. We'll video chat every week."
She let him go when she felt Oliver's hand on her shoulder.
"I'm so proud of you."
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During his time in college, like most freshmen, Zack focused on his grades. He went back home a few times, mainly during important holidays. Against his mom's wishes, he decided to come back home full time for the summer to work. She couldn't deny the fact it would be useful, even if she didn't want him to skip semesters, if possible. The earlier he would get his degree, the earlier he could start working a real job.
A week after he came back home, Zack had had a long Thursday at work, so he went to bed early. Oliver was staying in a motel overnight near his job-site. Since he had to move for his job, it wasn't rare for him to sleep there for a couple of days during the week if needed, instead of doing a three-hours drive.
Zack woke up in the middle of the night. He looked at his clock, it was a little after midnight. He got up to go to the bathroom. He tried to be sneaky to not wake anybody. After doing his business, he walked back toward his bedroom. On his way, he heard strange noises coming from his stepsister's bedroom.
Curious to identify the sound, he got closer. It started to sound like moans. When he was next to the door, he could confirm that it was indeed the sound of moaning, but it was mixed with clapping.
"
Is she with her boyfriend?
"
He had to admit that her moans matched her face. They were very erotic. His arousal started to grow. He looked furtively toward his mother's bedroom. What are the odds she will wake up during the five minutes it will take for him to jerk off if he put his mind to it?
He imagined the worst-case scenario. His mother would probably scold him, but she would understand why a healthy young man would be jacking off to the sound of his stepsister getting fucked.
He took his dick out and started pumping. Their rhythm changed from time to time, but it was always the sound of moaning and clapping.
Then he heard a slap, followed by "You like that, don't you? You big slut," over the moans.
"
Khloe?
" Zack didn't talk to her often, but he could still recognize his stepsister's voice. He wouldn't believe the moans he was hearing were not from a girl. "
So she's a lesbian... that's too bad for the male species.
"
Knowing she was with a girl didn't diminish his arousal. If anything, it was the opposite. He pumped his cock faster.
When he was getting close, he realized he didn't have any tissue. Just as he was about to leave, he heard something that blew his mind.
"You're really quiet today. You usually scream like a bitch in heat. Is it because your son is sleeping in the other room?"
"
She fucking my mom!?
"
Zack then associated the erotic sound he was hearing with his mom. He imagined her naked, with her ass in the air, getting fucked by his beautiful stepsister. He instinctively began to jerk his cock again, completely oblivious to what will happen when he would climax.
"It's a shame, because I like to hear you wail."
Both the clapping sound and the moans got louder.
"What would he think of you? Getting fucked like a whore while he sleeps in the other room."
He heard another slap. "Ah!"
"I bet he would love to know his mother is a big slut. You are, aren't you?"
"AAAH!"
"Answer me!"
Zack didn't know what Khloe did to make her yell, but his mom answered.
"Yes, I'm a big slut."
Zack blew his load on the door. Spurts of sperm splattered all over it. He could hear the lust in her mother's voice. It's a tone he had never heard from her before. His heart was about to explode. He had trouble breathing.
After a few seconds, he realized what he'd done. He silently ran to the bathroom and rolled out a big amount of toilet paper. He managed to calm down a bit.
He came back and started cleaning.
"Getting close? Are you going to cum all over your little girl's cock?"
"Hmm mmm."
*Slap*
"Say it!"
"I'm going to cum haaan... all over my little girl's haaan... cock."
"God damn, I fucking love to pound your ass."