Time to patch things up between the siblings.

Beth seems startled to find your girlfriend and her brother already inside, but what really sends her into catatonic shock is that Emma has her mouth around Franklin's cock. Beth hasn't seen her brother's dick since they were both very young, well before puberty. She never guessed he had grown up like this, and her eyes stay fixed on it as you lead her inside. He's not as long as you are, but he's got more meat on his bone, it's almost as wide around as your wrist. Beth is stunned, pure deer in headlights. Franklin's eyes are shut tight as he tries to survive Emma's 'enhanced interrogation', so he doesn't see you enter. Beth is holding you like a security blanket as you both sit down in the middle of the tent to watch Emma do her thing. Without dislodging Franklin's prick from her mouth, she looks up at you both and gives a sly wink. She slowly pulls back from Franklin with a long suck and a satisfying pop as her lips break the airtight seal on his cockhead. Franklin opens his eyes to see what's going on, and he and Beth stare at each other in bewilderment.

"Beth? How-- you-- what are you doing here?" H's startled and starts to sit up, but Emma has control over him. She's spent the last half hour slobbering over his dick, getting it nice and sensitive, and she's able to keep him seated with a steady stroking rhythm. He breaks off mid-sentence and relaxes again on his elbows, hypnotized with pleasure.

"Have you ever done this to a man before, Beth? It's the best way to calm someone down, you know." Emma lies on her side so that Beth can see everything: Emma's tits hugged tightly by her top, her brother's sizeable package, and the hand slowly making it twitch with a light touch. "I think what you need is a confidence booster. Try it out on John. John, why don't you lie down?" You oblige, and with some light encouragement Beth is kneeling between your legs, tentatively tugging at your trousers. She gasps a bit as your huge cock suddenly flops free of its enclosure, not even hard yet but still filling her entire hand as she nervously starts to stroke you.

"Don't be afraid of it, it's just a cock." Emma cheerfully instructs. "Think of it as your new best friend. Be gentle, but also confident. Nobody likes a half-hearted handjob. And look into his eyes, engage with him!" Emma demonstrates as much on Franklin, who lets out a low groan as she returns her full attention to him. He's still aware of what's going on, but he's down for some kinky fun as long as it doesn't go too far. Besides, his sister needs to learn to loosen up and be more of an adult about things. More than any of that, though, he's hoping he gets a chance to fuck your gorgeous girlfriend, and he'll put up with nearly anything for a shot at her. Besides, he thinks, Beth is actually kind of cute to look at, sister or on.

Beth seems to be putting some mental blinders on. She's definitely showing signs of excitement now that she's tugging on your cock, especially so soon after meeting you. It's a roller coaster of fresh feelings that's starting to do loop-de-loops now that she's sitting next to her half-naked brother, so she's trying her best to ignore it and focus on her own new experience. In her mind, she's not doing anything crazier than hooking up with some unattached single guy she just met. Just regular college stuff, right? You're almost fully erect now, and Beth is starting to use two hands to cover your whole length, copying what she sees in online porn. Emma sees her start to get into it and decides to move a bit further.

"That's it, that's really sexy! Now that he's completely hard, you should start using you mouth a bit. Start with your tongue, like this." Beth looks over as Emma takes a long, slow lick from the base of Franklin's shaft all the way to the top, tickling his head a bit at the end. Beth's face loses a bit of its luster and you can tell she's afraid to step it up. She licks her lips a couple of times, but can't quite bring herself to go down on you. Emma picks up on it.

"Here, maybe you'll be more comfortable with someone you know better." In a flash, Emma hops up and takes Beth by the shoulders, reorienting her body to plop her head right by her own brother's huge cock. Neither is quite sure how to react. Franklin's head is running over with all his younger fantasies of having sex with his sister, but he's trying hard to look detached and concerned. He manages a half-smile half-grimace, but Beth is suddenly feeling different. Now she feels like she isn't performing well enough, like she wants to impress you. She wants to prove that she isn't afraid, that she isn't just some frightened little girl, but a woman who can take pressure. With a determined look, she stares at you and Emma as she opens wide, as wide as she can, and takes Franklin's cockhead into her mouth.

"Yay, Beth, hooray!" Emma gives a little clap and cutesy celebration. Beth starts to bob her head up and down, letting her tongue and saliva thoroughly coat her brother's thick shaft as she works her way down, little by little. Franklin has dropped the act, he's starting to shift at the hips, feeling restless after all these years of admiring his sister. They're both breaking all the rules tonight, and it's starting to turn both of them on even more.

"I've always wanted to do this, did you know that?" He runs a hand through his sister's blonde hair. "It feels so great." Beth comes up for a second.

"Yeah? This is my first time blowing a guy, too." They exchange dirty grins as Franklin guides her head along his cock. Emma beams like a teacher who's watching her student ace an exam. She gets down next to Beth and helps her suck, whispering little tips in her ear about gently squeezing her brother's balls and using the tip of her tongue to tickle his urethra. Soon, Franklin's dick is a mess of spit from both girls, and he's dribbling precum all over his shorts. Emma and Beth take turns sucking him, Beth doing her best to suck him all the way down, and Emma effortlessly taking him deep in her throat. He starts to breathe deep and sharp, and Emma knows that he's about to cum. Franklin is thinking about his innocent sister that he's known since childhood, that he always tried to protect from anyone who would hurt her, and how much he loves her, and just how fucking nasty he wants to get with her tonight. He imagines her pretty face spattered with his cum, and then opens his eyes to find his dream coming true. His cock erupts with pearly jizz, shooting ropes across Beth and Emma's faces, shuddering as he does. Normally, Emma wouldn't waste fresh cum like this and would start licking it off immediately, but she senses something more important is happening here.

Beth is frozen, mouth agape. Her own brother has just shot his load on her face, like she's some common whore from the cheerleading squad. And she loves it. This is the turning point for her, as she realizes that she can do anything, take part in any pleasure she desires. She licks cum off of her lips and savors the taste, and looks deeply into her brother's eyes with a renewed passion. You decide to reintroduce yourself to the proceedings, because you won't let them quit while there's still so much to try. You position yourself in between Beth and Emma, and gesture for both of them to spin around and show off their asses. Both still have their swimsuit bottoms on, and Beth revels in her new naughtiness by wiggling her ass sensually. You slowly peel off both swimsuits with your hands, revealing two aching pussies in **** need of rock hard dick.