All characters in sexual situations are 18 or older. Thanks for reading!
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Jackson lay in bed watching an action movie on his computer monitor. Frustration filled him. His fingers squirmed inside the bandages that wrapped each hand. His mom had given him a handjob just the day before, but it felt like it'd been weeks since he'd last cum. His balls ached, and his chemically enhanced dick bobbed slightly under the blanket with his pulse. He tried to focus on the movie.
"Hey, there." Violet swept into his room wearing yoga pants and a tank top. "How's my favorite brother?"
"I'm your only brother." Jackson turned his head and frowned at her. "And I don't feel so great."
"No?" Violet carried a large glass beaker in her hand. She walked over to the computer, grabbed the mouse, and paused the movie. "What seems to be the trouble?"
"My balls hurt." Jackson wasn't normally crass, especially with family. But he was very grumpy. He was thankful, however, for the invention of yoga pants. He eyed her trim butt as she bent over to move the mouse. It was almost like she wasn't wearing anything at all. Jackson then looked away. He wasn't supposed to look at his sister like that.
"I see." Violet moved her tall, slim figure across the room and sat down on the edge of the bed near Jackson's hip. "I was afraid of that. The mass distribution side effects."
"The what?" Jackson stared at her modest boobs hiding in her tank top. He just couldn't help himself.
"When did you become such a perv? Eyes up here." Violet pointed to her own brown eyes. "That's better. What I meant was that when you got Serum 42 in your bloodstream, you got a heavy dose. If we're lucky, your synapses will reamplify. But there are other cellular reorganizing properties to the current version of the serum."
"I don't understand." Jackson shook his head on the pillow.
"What I'm trying to say is, your junk went into hyperdrive when you got that blue stuff in the cuts on your hands." She placed the beaker on his nightstand. "I'm working on a formula to counteract Serum 42, but I need a sample from you to do the work."
"A sample of what?" Jackson had a hard tone to his voice.
"Where's my adoring little brother? Who are you and what have you done with him?" Violet tried to smile. Maybe irritability was a side effect of the serum? Violet made a mental note to follow up on that.
"Just tell me what you need, Violet." Jackson sighed in exasperation and his eyes fell down to her petite boobs again.
"Maybe I should come back later." Violet put her hands together on her lap and absentmindedly picked at one of her chipped fingernails.
"Whatever, just put my movie back on." Jackson tried not to think of the dull steady ache in his bloated balls.
"I need a sperm sample, okay?" Violet looked over at the elf princess poster above Jackson's bed. The elf was quite the zaftig lady in a flowing dress with a thin crown on her brow. A dragon curled up next to her and she had her hand on its large head. She's tamed the beast, Violet thought. "The next time you're... um... executing manual override, just save me some stuff."
"I won't be doing any manual override for a while." Jackson held up his bandaged hands. "Remember?"
"Oh, sorry. Of course." Violet looked at his poor hands and then at the pained expression on his face. "Oooohhhhhh. Is that why you're so grumpy? All backed up?"
"Sorta." Jackson shrugged and put his hands back down on the blanket.
"I'm so sorry." Violet blushed. "Chad gets cranky when it's been too long, too."
"Fine, can you turn the movie back on?"
"But I need the sample for the new counteractive serum." Violet's eyes crept down her brother's bed until they rested on the lump under the blankets. She had already seen what Serum 42 had done to him when he was soft. But what did that monster look like hard?
"Then you're going to have to do it." Jackson gave her a hopeful look.
"Wow. No way." Violet put a hand to her mouth. "Gross, Jackie. How could I... You're my... um... and... I'm your... and I'm not cheating on Chad." Her cheeks went from rosy to a deep red.
"I won't tell your boyfriend."
"I... I..." Violet looked over her shoulder at the open bedroom door. She stood and walked across the room.
"Violet, don't go." Jackson watched her with concern. Her slender legs looked so inviting in those yoga pants. To his relief, instead of leaving, she closed the door and locked it. She then returned to his bed and sat down next to him.
"If you tell anyone about this, you are so dead." Violet took hold of the blanket and slowly lowered it down her brother's body. The massive head of his cock came into view and she gasped. Then the thick, veiny shaft appeared inch by inch. Finally, his tumescent balls were revealed. "Wow. My formula really did a number on you." She folded the blanket over his legs. "I've never seen anything like it." Her fingers trembled as she reached for her brother's dick. She wrapped her hands around the shaft. "It's so... warm."
"God... that feels so good."
"I'm only doing this for science," Violet whispered. "And to help you... with the side effects." Her hands moved up and down the lengthened penis. "I'm so sorry this happened to you, Jackie." But a part of her wasn't sorry at all.