**Please read the preceding parts, I’ll link them in the comments. If you don’t, a lot of this won’t make much sense.**
Things were going swimmingly for the twins. It had been almost a week since Katie’s pool party, and they had not only forgiven each other, they had launched a full-on sexual relationship. Honestly, it was more like a deal, and on Monday they had discussed the terms:
“I think we should just be naked all the time,” Katie suggested, “it keeps me in the mood, and I just like looking at us.”
“Agreed, most of the time, except for when I want to dress up before we do it,” Karen rebutted. “Also, I think each of us should initiate whenever we want it, no holding back.”
“I think so too,” Karen said, “but you’ve gotta give me at least 15 minutes after sex before initiating again.”
“Can do, but I get to decide whether you cum in me or on me, and no mouth kissing. We’re not lovers, just sisters who fuck,” Karen stated, very matter-of-factly.
And so it was settled. They would retain their new relationship as sisters and friends, but they would be available to fulfill each other’s needs. There was only one problem, they had a lot of needs. They fucked six more times on Monday, four times on Tuesday, six on Wednesday. They tried every position they could think of, or rather every position Karen could think of, which was a lot. They slept in the same bed, took showers together, and sat on each other’s laps when they were watching TV. Neither could think of anything more fun to do, so they mostly just sat at home for the week. Wednesday night they decided to go for a rough session which left Katie sore in the morning. Karen woke up and started stroking Katie’s aching cock, so she spoke up. “Look, this is great and all, and I wanna keep doing it, but you’re wearing me out, Karen. Can we have a little more time between sessions?” Karen didn’t seem offended, she just said, “sure,” and got up to eat breakfast.
The morning passed by, each one either reading or doing other things around the house, and around noon Katie offered to drive into town to get lunch. Since she was in the habit of taking risks lately, Katie decided to drive her convertible with the top down, naked. The breeze whipped through her hair and made her nipples hard, and everyone she passed couldn’t help looking at her gorgeous breasts. *This is the life*, she thought. She went through the drive through of her favorite burger place. The guy at the first window tried to hide his embarrassment by looking anywhere else once he saw her tits, and the girl at the second window almost dropped the food when she saw Katie’s cock. She looked aroused and confused, and that look had started to feel like signing autographs for Katie. Katie paid in cash, she wasn’t feeling *that* lucky. She basked in the glow of her own pride on the way home, and almost didn’t see a cop in time to slow down. *What am I doing?* she thought, *I really need to be more careful.*
She walked through the front door and called out, “Karen, I’m home with food!” But Karen didn’t answer. Katie walked into the living room and saw that the patio door was open, so she went outside to see her sister swimming around lazily in the pool. She repeated herself, “I’ve got food.” “I see that,” Karen replied, “leave it on that table, I’m almost done swimming.” Katie sat the food down on the small table she kept her tan lotion on beside her tanning chair, then sat down and started eating her cheeseburger. She watched Karen swim back and forth, saw her butt bob above the water every now and then, and realized she was wearing the tiny bikini from Saturday night. Katie felt her cock begin to swell as she took the next bite. “You know, we’ve had this pool forever but I’ve only been swimming like, twice?” Karen shouted out. “Yeah, me too,” said Katie, “but for obvious reasons I guess”, she chuckled.
Karen started to climb out of the pool at the far end from Katie, and as she cleared the ladder Katie realized just how stunning she really looked in that bikini. Her breasts were bulging out of the top on all sides, the bottom barely covered her pussy, and when it got wet it clung to every bump and crevice. Beads of water had gathered all over Karen’s firm body, and several were streaming down her perky tits and ever-so-slightly toned stomach. Katie wanted to be those droplets. As Karen approached, she started untying her top, and then let it fall off of her. *Oh fuck,* Katie thought. She didn’t need the slow motion, that was happening in her mind. Karen walked right up to the front of her reclining patio chair, and Katie smiled and said, “you’re doing *Fast Times*, aren’t you?” “I am,” Karen said, and gestured to her sister’s now fully erect cock, “why aren’t you?” Instantly robbed of the sweetness of Karen’s gesture and filled with heart-pounding lust, Katie breathlessly said, “oh, uh, o-okay.” She grabbed a little lotion and started stroking, but she was somehow too nervous to regulate her speed, like she had never done this before.
Karen reached into the fast food bag and pulled out her own cheeseburger, sat on the front of Katie’s chair with one leg on either side, and started to unwrap it. “What are you doing?” Katie asked. “You got your dinner and a show, now I want mine,” Karen said, “Now, go slow.” So Karen ate her cheeseburger and watched Katie stroke herself. Katie kept making nervous eye contact, occasionally breaking to look at Karen’s tits. Last time they were in this situation, Katie was terrified and ashamed and humiliated and all sorts of things, and that was certainly on her mind, but this time was cathartic. Masturbating for her sister felt like loading a lifetime of shame into a t-shirt canon and firing it into a crowd. She wanted to go faster, but she wouldn’t disobey her sister’s commands.
Karen finished her burger and started to stand up, “I think I’m gonna tan for a bit. You mind helping me with the lotion?” Katie exuberantly said, “yeah, sure!” but struggled to remove her hands from her throbbing cock. Karen moved the next chair into full reclining position and laid down on it, face up, putting on some sunglasses. “Come on, we don’t have all day,” she scolded. Katie jumped up and grabbed the lotion, and moved over to Karen’s nearly-naked body, still feeling nervous somehow. It was like she had forgotten how to exist and needed to be told what to do. Karen was happy to oblige that need, “well, sit on my lap and lotion my chest.” Katie obeyed, and sat on Karen’s amazing thighs, and let her balls sink down into her thigh gap. As she did, the underside of her rock-hard cock pressed into the front of her sister’s pussy, and she could almost feel her lips part beneath the thin fabric of her bikini. Karen pretended not to notice, looking cool as a cucumber beneath those sunglasses. Katie put some lotion onto her hands and started rubbing it onto Karen’s stomach, her shoulders, and her breasts. She spent extra time on her breasts. As Karen’s glistening skin began to soak up the last of the lotion, Karen commanded her again, “alright, that’s enough, move down to my legs.” Katie did, she stood up, got more lotion and started rubbing Karen’s thighs and calves. “Aren’t you forgetting something?” Karen said in a condescending tone. Katie timidly moved up again to her sister’s hips, and started rubbing in lotion anywhere she hadn’t reached yet. “Don’t forget to get under the straps,” Karen teased. Katie followed, and slid her fingers underneath the straps of Karen’s bikini, then toward the triangle of fabric, getting dangerously close to her pussy. “Hold on there, cowgirl,” Karen teased, flipping over onto her stomach, “You’ve gotta get my back too.”
This was too much for Katie. She felt like she was gonna burst at any moment, but she kept following Karen’s orders. She sat on her sister’s thighs again, nuzzling her balls into Karen’s thigh gab, and resting her now throbbing cock between her ass cheeks. Karen’s ass twitched slightly, and Katie had to catch her self not to cum immediately. After breathing for a moment, she started lotioning Karen’s back, then her thighs again, afraid of touching her ass until she was told. Karen looked over her shoulder, “Hey, take off my bikini since it’s clearly getting in your way.” Katie grabbed the bikini bottom’s straps at the hips, and slowly slid them all the way down Karen’s legs. She stood with one leg on either side of the chair. Then she started rubbing lotion all over her sister’s ass. She did so for several minutes, enjoying Karen’s ass like nobody had enjoyed any ass ever before. Karen looked back again with a sadistic look in her eye, “I think you missed a spot on my shoulders.” Katie knew she couldn’t take another second of Karen’s ass on her cock, so she stepped forward but remained in a standing position, and started rubbing lotion on her shoulders. Karen looked over the other shoulder, “why are you being weird?” she smirked, “sit down.” She knew exactly what she was doing. Against her better judgment, Katie sat down, allowing her cock to wedge itself between Karen’s ass cheeks again. She could feel the heat from Karen’s pussy against her balls. Katie was literally holding her breath not to cum as she lotioned her sister’s shoulders. That is, until Karen began to cruelly rock her hips.
Karen’s cheeks slid against her sister’s cock so perfectly, and her pussy felt so warm against Katie’s balls, Katie came buckets all over her sister’s back. Katie sighed in relief, and Karen in mock relief. “Alright, my turn,” Karen said, shifting her knees forward enough to raise her ass off the reclined chair. Still facing downward, she reached between her legs with both hands, grabbing Katie’s cock with one hand and her balls with the other. She began to force Katie’s still-erect cock into her pussy. All the touching felt awful on Katie’s now extremely sensitive cock, and she cried out, “Wait! Stop! You said you’d wait 15 minutes before starting again!” “I said I’d wait 15 minutes *after sex*,” Karen said, mockingly, “I don’t think we’ve had sex yet. Now, fuck me, and do it hard.” Katie had no choice, at least that’s how she felt. A powerful physicality suddenly came over her, she grasped Karen’s hips and she drove her entire cock in a single thrust. It was incredibly painful, but Katie pushed through it. She grabbed Karen’s wrists and used them like handlebars as she pounded her body into the chair over and over. Katie fucked Karen so hard the patio chair broke from underneath them, and she still kept pounding, pushing her sister’s face into the ground. Ten minutes later, Karen came so hard she started sobbing, and cried out, “okay, okay, stop! I’m done!” “*I’m not,*” Katie returned. Karen had made a terrible mistake. In forcing Katie to fuck through the pain, she awakened something primal, and Katie continued to pound her spent pussy for another hour.
Finally Katie came, and since Karen broke the rules she did too, pumping every ounce into Karen’s beautiful limp body without asking. Katie stood up, quickly rubbed lotion all over herself, everywhere she could reach, and laid down on her own chair to tan.
*This story is entirely fictional, and any real names are entirely coincidental.*
Source: reddit.com/r/sexystories/comments/7xjnpn/pool_party_3_home_alone_inc_nc_futa_fdom
[Part 1](https://www.reddit.com/r/sexystories/comments/7wymu5/pool_party_inc_nc_oral_futa_mast_huml_exh_blkmail/)
[Part 2](https://www.reddit.com/r/sexystories/comments/7x186f/pool_party_2_sisters_inc_nc_oral_futa_exh/)
[Part 3](https://www.reddit.com/r/sexystories/comments/7xjnpn/pool_party_3_home_alone_inc_nc_futa_fdom/)