All characters in sexual situations are 18 or older. Thanks for reading!
"How's my favorite brother this fine morning?" Violet swung Jackson's door open quickly and stepped inside. Was she hoping to catch him with his dick out? She wasn't sure. That was a disturbing thought. She pulled at the sleeves of her white lab coat with trembling fingers. Being nervous around Jackson was very new to her.
"I'm your only brother, duffus." Jackson looked over at his sister from his desk chair. He clicked on the mouse and paused his game. "Any luck with the counterwhatsit?" Despite the constant ache in his balls, he hoped she'd say no.
"Not yet." Violet closed the door behind her and stepped into the room. "Oh, don't look so sad, Jackie. We'll figure this out." She clasped her hands in front of her and fiddled with the beaker in her left hand. "So... um... about that. I need another sample."
"Okay. Give it here." Jackson held out his hand for the beaker and placed it on his desk when she handed it to him. "I'll fap one out after I colonize the outer region in sector 13."
"What?" Violet blinked her hazel eyes in confusion.
"In my space game, Vi." Jackson looked back at his game. "Probably in an hour or so." He un-paused the game and diverted resources into seed ships at the main space dock.
"Did you say fap?" When had her nerdy, eighteen-year-old brother gotten so cavalier about sex talk? He seemed so... confident.
"Yeah. My hands are fine now. So, I'll take care of it myself. You're off the hook. See ya." He didn't look up from the computer screen.
"Um... Jackie?" Violet rolled the toes on her left foot slowly on the floor. "Maybe... maybe I should help you again."
Jackson paused the game and slowly looked over at his big sister. "You want to help?"
"Yes." Violet cleared her throat and looked away. She couldn't meet her brother's gaze. "I just... I just think that... scientifically..." her eyes moved to his lap and the growing lump in his shorts. "... I should observe... um..."
"Well, screw sector 13 then." A big smile spread on Jackson's face. "Get over here."
Violet stepped over to her brother and dropped to her knees.
~~
The tray in Lucy's hand held three turkey sandwiches and a big glass of milk. She hummed as she climbed the stairs. Poor Jackson had been so hungry lately. Lucy hoped Violet reversed the serum soon. Her dress swished as she reached the top of the stairs and turned down the hall. She stopped outside Jackson's room and put her ear up to the closed door. It sounded like he was watching porn again. She could hear a woman's voice mewing and grunting. That poor boy couldn't empty those weighty testicles enough.
Lucy put her hand on the doorknob, balanced the tray with her other hand, and paused. He wouldn't mind if she had a little peek. She wanted to see which video her son had picked. There were lots of surprising developments in the Burton household recently. One of them was Lucy's burgeoning interest in porn. She supposed she'd never had the opportunity before. She couldn't very well watch with her husband, Delmore.
The door swung slowly and quietly open. Lucy peeked into the room and almost dropped the tray when she saw what was going on in there. Her skinny son sat in his desk chair facing the far window with his shorts around his legs. His impossibly long penis exposed and in his big sister's right hand. Violet's left hand was stuffed between her legs, but her lab coat obscured what she was doing with that hand. The way Violet's mouth hung open, the grunting sounds she made, and the far-off look in her eyes let Lucy know exactly what her hidden left hand was up to.
When was the last time Lucy had taken a breath? She exhaled and then inhaled deeply. Her children didn't notice her as she stood there peeking in. They were busy. Violet masturbated herself and Jackson. Lucy's brain tried to wrap itself around this insane act. She quietly closed the door and leaned against the wall, breathing very hard. It wasn't just Lucy, it was Violet, too. What was happening in her once-quiet, suburban home?
Without thinking, Lucy walked quickly to her room. She put the tray of sandwiches on her dresser, closed and locked her door, and flopped onto the bed. Like lightning, her hand moved between her legs, pulled up her dress, and pulled her wet panties to the side. It was the most furious masturbation session the middle-aged wife had ever had.
~~
His sperm looked different. Violet blinked into her microscope. The difference was clear as day. The little guys swam faster than they should and they wiggled at a greater pace. Violet suddenly felt a little weak in the knees thinking about how much of her brother's cum she'd already swallowed. This stuff was inside her.
What did the changes in sperm mean? Violet had her suspicions. Increased fertility was likely for sure. What else?
