All characters in any sexual situations are over 18. This is a concluded, separate story, but it's a sequel. The characters are introduced more in the first part.
This story is about an intense piss fetish and incest between sisters. There are diapers for peeing, and there is much focus on immature games and dialogue. It can be a bit over-the-top. Skip it if you think this is not for you.
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When Anna and her little sister Mia first fell in love, they soon discovered that society could really throw some serious wrenches in the works of a little innocent incest.
Their roommates, for example, made privacy ridiculously difficult to come by. And leaving the apartments for some public sneaky kissing often made things even worse. Heads would turn everywhere to check out two blond female college students in their early 20s with fine breasts and asses, and in your hometown, any onlooker could mean the end of a shameful secret.
Either way, Anna and Mia didn't want to settle for sneaky flirts and teases. These girls wanted some serious sibling cunt, and the obvious solution was to move to a place of their own. Since available apartments were scarce mid-season, there was no choice but to resign themselves to no fucking through winter and spring.
"I'm desperate," Mia complained one day right after exams. "I'm so fucky! It doesn't matter how much I fuck myself anymore. I need sicker. I need to be an incest whore! I'm addicted! It won't go away."
Anna couldn't have put it better herself. They were perverted in the same way, craving all kinds of nasty and depraved fuck-games for proper satisfaction. On top of that, the sisters found each other very attractive, physically, and incest gave them the slutty thrills they needed. Now, they were slowly going insane with frustration.
Then came the miracle.
A favorite band was giving an early summer concert just a few hours away by the coast, and the arena was close to their grandmother's very pleasant apartment. It turned out that their spunky 75-year-old gran was leaving for a week at a resort with a friend, and she was willing to lend her home to her granddaughters over the weekend if they could get there in time.
They arrived at their gran's place a late Friday afternoon during one of the worst heatwaves in years. Two packed suitcases met them inside the door. The large old woman was booked on an evening plane, and there was time for a quick cup of iced tea between grandmother and granddaughters before the girls helped their gran down the elevators and into a taxi.
Finally, they were alone.
Compared to the rest of the family, their gran was rich, and her apartment was a magnificent single penthouse on top of a complex. There were windows everywhere, and a spacious balcony was carved into the slanted tin roof, allowing you a view down on a hundred other apartments and a courtyard.
"We are now queens in our queendom," Mia proclaimed theatrically, and then she turned to give her sister a first kiss on the lips. "Queens can kiss their sisters. I'm sure."
"Oohhh, fuck Sis," Anna panted. "Are we gonna do it already? We have time for a quick one. But, she's barely left. It's like, a little weird still, isn't it? Maybe we should relax a bit."
They spent a few moments trying to figure out how to enjoy themselves best, playing queens while they sipped glasses of Gran's wine and looked down at their realm. There was no need to rush things.
Anna made a discovery during her next trip to pee.
"I always thought age would never get to Gran," she called out from the bathroom. "Look what I found. It's full of these really big diapers. Do you think she uses them?"
There was a whole cupboard almost filled with stacked diaper packs in the bathroom. One pack on top was open. A more detailed inspection revealed that they were some sort of ultra-absorbent, extra thick incontinence pads. To hold them in place, you had to use extra large panties of which there were a few in the cupboard and some more in the wash basket.
"I've never seen her wear them, but maybe at night," Anna observed to her sister, joining in. "Jeez, Gran is huge. You could fit both of us in one of these."
Anna was lifting up her gran's panties from the wash basket, holding them out, inspecting their size. Their grandmother was a big lady, and her ass was clearly enormous compared to those of her descendants.
"What were you saying about being weird at Gran's place?" Mia giggled. "Now, you're playing with her dirty panties."
They were indeed inspecting the large diaper-panties, and both girls were equally fascinated.
"Ohh, I'm such a whore for getting wet by this," Anna admitted. "Can you imagine Gran has wet herself in this?"
In the mean time, Mia dug out a regular panty, which was smaller but still made for an enormous ass.
"Yeaahh," she agreed with lust in her eyes, inspecting the dirty piece of underwear. "I feel it! This is creaming my cunt, Sis. Do you think her cunt leaked pee in this, too? Do you think we can smell Gran's cunt in here?"
Their pent-up frustration finally bubbled over. Mia held the crotch of the panty to her nose and smiled. Anna giggled and approached her sister. Soon, both of them were smelling the crotch of their grandmother's dirty panties, and they kissed through the fabric. Their mouths opened, and both their tongues licked the dirty panty crotch.
"I want to taste your cunt spunk Sis," Anna panted. "I'm a sick fucking whore. I've wanted to suck your grool for so long. My cunt is fucking slimy right now!"
"Aaahhh, but what about respecting Gran's privacy?" Mia teased with a playful smile through the panties. "Don't you think she'd be disgusted by incest in her apartment? Besides, we can't fuck now. We'd miss the show."
She was right about the last part. They had plenty of time to figure out how to fuck each other senseless later, but right now they had serious business to attend to.
