Over the next few days, Jennifer’s fantasies involving Becky and Nate only continued to develop, thanks largely to her checklist app. On Monday, she earned more points for masturbating while imagining Nate and Becky fucking behind her back. When Tuesday came, one of her tasks was to fuck Nate while roleplaying that she was Becky. Wednesday brought a prompt to imagine making out with Becky while Nate fingered them both. With each prompt, Jennifer found herself enjoying the fantasies involving her sister more and more.

The fact that Becky seemed to need Nate’s help every night only fueled Jennifer’s fantasies. One night, Becky asked Nate to come over to help hang some pictures. The next evening, she needed help with her computer. Jennifer wasn’t even sure what she’d needed on Wednesday, only that Nate said he was going over there and he’d be back soon. Imagining that Nate was actually there to fuck his aunt, Jennifer furiously masturbated every time he left.

On Thursday morning, Jennifer awoke to memories from a night full of salacious dreams. Dreams about fucking Nate. Dreams about watching Nate fuck Becky. She even had dreams about fucking Becky herself. Every dream encounter was hotter than the last, to the point that Jennifer’s pussy was already leaking as she rubbed the sleep out of her eyes. Rolling over to face her son in bed, she smiled, knowing exactly what she needed.

Jennifer managed to coax three loads of cum out of her son before he headed out the door that morning. She smiled as she watched him leave, eager to pick up where they left off later that night. With her checklist loaded on her phone, she hopped in the shower to clean herself off and continue earning points toward the next level in the app.

About an hour before she was expecting Nate home, Jennifer heard a knock at the front door. She quickly slipped on some clothes and rushed to the front door. As she swung the door open a moment later, she was surprised to see her sister standing there.

“Becky!” Jennifer exclaimed, stepping on the porch and giving her sister a hug. “What are you doing here? I thought you worked today.”

“I, um, actually called in sick,” Becky admitted. “It’s just that I had… things to get done. Can I come in?”

“Of course,” Jennifer smiled, ushering her sister into the living room and closing the door behind them. “What’s up?”

She and Becky chatted as she guided them over to the living room sofa, where they each took a seat. As they continued chit-chatting, Jennifer could feel her heart pounding harder in her chest. She’d spent so much time over the last few days fantasizing about Becky in sexual situations. Now that she was sitting right in front of her on the sofa, it was hard not to just reach out and grab her.

Jennifer’s eyes briefly scanned her sister’s body as Becky changed the topic, discussing her progress with Nate’s Checklist app. Becky was six years younger than Jennifer, and Jennifer always thought of her as “the pretty one.” Today, though, she was beyond pretty. Today, Becky was sexy. From her makeup and the way her blonde hair draped her face to the adorable pink top she was wearing that showcased her generous tits, everything about her sister screamed raw sex appeal.

“...and Nate was super impressed that I was already up to level fourteen last night,” Becky continued as Jennifer’s eyes rose to meet hers. “In fact, I’m just one task away from reaching level fifteen.”

“Really?” Jennifer asked. “That is impressive. I’ve been using the checklist app for a week longer than you, and I’m only up to level twenty-three. At this rate, you’re going to catch up with me in no time. So, what do you have to do to get up to level fifteen?”

“That’s actually why I was here.” Becky fidgeted a little as she spoke. “The app seems like it really wants me to do this one thing. It’s not giving me any other tasks, even though I’ve refreshed the page a dozen times. At first I wasn’t so sure about it, but now, I think I want to do it.”

“I know what that’s like,” Jennifer admitted. As she spoke, she felt herself getting a little more turned on, remembering the last time that happened to her and how she and Nate started fucking as a result. “In my honest opinion, the best thing you can do is just follow the instructions and earn the points. I know I’ve never regretted it.”

“Yeah,” Becky breathed. “I know I’d like it. It’s just a big step.”

“I can tell you from personal experience,” Jennifer began, getting more turned on as she thought back to the first time she let Nate ride her to an orgasm, “the big steps are really the best steps.”

Becky nodded. “I think you’re right,” she said, a smile growing on her lips as she moved in closer to her sister. “In fact, I know you’re right.”

Before Jennifer could respond, Becky dove forward, pressing her lips against her sister’s. Jennifer’s eyes shot wide open, briefly shocked at her sister’s actions. Almost instantly, the fantasies she had been experiencing over the past few days returned to her. Realizing how much she’d been wanting this, Jennifer found herself melting into her sister’s kiss.

In short order, Jennifer began kissing her sister back. As their makeout session grew more and more passionate, Jennifer felt Becky’s lips parting and her tongue tentatively entering her mouth. Jennifer let out a moan, her own tongue moving to meet Becky’s. In no time at all, their tongues were dancing as the women moaned and groaned into each other's mouths.

It didn’t take long after that for Becky to start tugging at Jennifer’s top. Picking up her sister’s cues, Jennifer raised up her hands, allowing the kiss to break off long enough for Becky to pull her shirt up and over her head. Jennifer helped Becky out of her blouse as well before they resumed making out.

“Oh, God,” Becky moaned between kisses. “I want you so bad, Jen.”

“I want you, too,” Jennifer groaned as Becky started kissing a trail down her neck.

Jennifer wrapped her arms around her sister, her fingers working open the clasp of her bra. Becky followed suit, and soon the women’s bras joined their shirts on the floor as their lips met once more.

“Come on,” Jennifer groaned, pushing Becky up and taking her by the hand. Jennifer practically dragged her sister up the steps toward her bedroom. A moment later, they were in Jennifer’s bed, with Jennifer lying on top of her sister, kissing her passionately as their hands explored each other’s bodies.

Slowly, Jennifer started trailing her kisses down Becky’s body. She started at her neck, eliciting a moan of pleasure from Becky as she alternated between kissing, sucking, and nibbling. Next, she made her way down to her collarbone, then lower still, until she was kissing her sister’s breasts. Becky let out a groan as Jennifer took one of her nipples into her mouth, suckling it for a moment before moving on.

Jennifer let one of her hands take up where her mouth left off, playing with Becky’s tits as she continued kissing lower and lower. When her kisses reached the top of Becky’s skirt, she flipped the skirt up and began kissing her sister’s thighs, kissing every inch along her panties. Jennifer could smell Becky’s arousal as she continued kissing her thighs. Becky groaned and moaned, telling her sister that this felt so good and begging her for more.

After a minute, Jennifer gave Becky more. Bringing her hands to her sister’s panties, Jennifer pulled them down and off, revealing her sister’s freshly shaved pussy for the first time. Jennifer's own pussy began to drip as she approached her sister's slit. It was so sexy. It was so inviting. For a moment, Jennifer just hovered over her sister, taking in the sight and smell of her arousal.

When she couldn’t take it anymore, Jennifer lowered her head, planting kisses up and down along the edges of her folds, teasing her with expert precision. Becky moaned, letting one of her hands run through Jennifer’s hair. Jennifer continued teasing, kissing up and down along Becky's pussy lips once more, barely brushing them with her lips.

“Fuck, Jen,” Becky moaned. “Eat me. I want it so bad.”

Jennifer smiled, briefly turning her head to look her sister in the eyes. “Is this what you want?” she purred, turning her head back down and drawing a long, slow lick between Becky’s pussy lips, parting them slightly with her tongue.

“Oh, fuck, yes,” Becky moaned. “More.”

Jennifer slowly drew her tongue up Becky’s pussy once more, eliciting more moans of pleasure from her sister. After a brief pause, she licked her again. Then again. Soon, the individual licks started melting together, like individual notes becoming a melody. Jennifer began lapping up her sister’s pussy, eating her out with a passion driven by days spent fantasizing about this very moment. Becky cried out in pleasure, telling her sister how much she loved this and how talented she was at eating pussy.

Next, Jennifer worked her way up to Becky’s clit, flicking and licking it with her tongue as Becky’s moans grew stronger. Jennifer groaned as she continued servicing her sister’s clit, loving the tastes and smells she was experiencing. Adding to Becky’s pleasure, Jennifer brought two of her fingers to her sister’s entrance and began pumping them inside her as she continued working her clit with her tongue.

“Oh, Jen! Oh, God!” Becky cried out. “I’m coming!”

Jennifer felt Becky begin to quake under her. Withdrawing her fingers from her pussy, Jennifer replaced them with her tongue, lapping up her juices and groaning as Becky shuddered beneath her in orgasm.

As Becky started coming down from her orgasm, Jennifer slowly crawled up in the bed until the two girls were nose to nose. They smiled at each other for a few seconds, and then Jennifer pushed forward, capturing her sister in a deep, passionate kiss as she wrapped her arms around her. The two remained like that for a minute, entwined and passionately making out with each other. As they finally broke off the kiss, Becky gave Jennifer a warm smile.

“That was amazing,” she admitted. “You were right; it was worth it.”

“I told you so,” Jennifer grinned.

“And now I think I’m going to return the favor.”

Jennifer lay back, letting out a delighted sigh as her sister removed her skirt and panties. Jennifer spread her legs, draping them over Becky’s shoulders as her little sister started eating her out. For the next several minutes, Becky reciprocated, licking and lapping at Jennifer's folds, causing the woman to emit moans and groans. When Jennifer finally had her orgasm, Becky was sure to lap up as much of her sister’s juices as she could, savoring the taste.

For the next hour, Jennifer and Becky lost themselves in each other’s arms. They kissed, they licked, they fucked, and they came. As they caught their breath between rounds, Becky and Jennifer shared even more secrets. Becky admitted that she’d been calling Nate over for more than just help around the house. As big and handsome as he was, she couldn’t help getting her hands on her sexy nephew. In turn, Jennifer admitted that she, too, had been taken by Nate. Becky was a little shocked at first but quickly found herself getting turned on by the thought of Nate coming inside the pussy she’d just finished eating.

Becky and Jennifer were busy making out when they were both startled by the sound of someone clearing their throat. Looking up from each other, they saw Nate, standing in the doorway of Jennifer’s room, smiling at them.

“Well, hello, ladies,” Nate grinned. “Am I interrupting anything?”