Let her get a feel for things.

"Can I, {Firstname}?" Joan asks again, her eyes shining with her eagerness as she stares as your exposed cock, her cheeks flushed with excitement as she takes in what undoubtedly her first erect penis. "Can I please touch it?"

"Yeah, go ahead," you tell her softly, nodding your head in encouragement as your eyes rake over her svelte young body in just her baby blue bra and panties. You want to see her naked, to take in the full glory of her tender young body... but there's time. We've got all day together, you assure yourself, forcing yourself to be patient. Plenty of time to see her naked, you smile as you watch her slowly move her hand, her fingers trembling nervously as she tentatively reaches out for your hard cock.

"Oh," Joan gasps as her fingers lightly run up the veined shaft of your manhood, her touch so light that it tickles. "It's... it's so hot, and... and smooth," she stammers, her eyes shining with her excitement as she gradually grows bolder, her touch becoming more sure as she moves her fingers over your cock. She glances at you nervously as she hesitantly wraps her fingers around your shaft, feeling the girth of your cock as she starts to move her hand up and down, stroking you. It's hot to see but her touch is so light, so soft, that you can barely feel her skin against yours.

"You don't have to be so gentle, Joan," you tell her softly, encouraging her with a nod of your head.

"Sorry, John, I've... I've never done this before," your younger sister stammers, blushing cutely as she tightens her grip. She's a little over-exuberant, tightening her grip until she's got your cock in painful **** grip.

"Easy, easy," you hiss, grimacing in pain.

"Shit, I'm... I'm so sorry," Joan gasps, her eyes going wide, her lip starting to tremble as if she is about to cry. "I'm... I just don't know what I'm doing," she almost sobs as she lets go of your cock.

"Hey," you say with a gentle smile, reaching out for her hand, "don't worry about it. That's what I'm here for... to teach you," you assure her, taking her hand and gently pulling it back to your cock, closing her hand around your shaft, your hand covering her's, showing the right amount of pressure to use. "There, just like that," you say, guiding her hand up and down in a slow steady pattern.

"Wow," your younger sister whispers as she starts to jerk you, your hand falling away from hers as she becomes used to the sensation of your cock in her hand, letting her set the pace. "Like this, John?" She asks, varying her speed and length of strokes.

"Mmm, just like that," you sigh, leaning back on the couch in pleasure as she grows more confident in her actions. "How does it feel?" You ask curiously, your hips starting to rock slightly in time with her strokes, your pleasure growing with each motion of her soft hand.

"It... it feels good," Joan assures you with a shy smile, looking up at you as she continues to jerk you off. "It feels naughty, John," she almost whispers to you as she squirms on the couch, shifting her position slightly. "It's really naughty and I'm enjoying it," she assures you with a timid little laugh as she shifts her position on the couch, spreading her legs a little as she turns her body to face you. You can see a telltale dark spot on the center of her panties.

"I can tell," you murmur as you stare at the moist spot spreading over her crotch. She's obviously enjoying this, you think with a smile, almost as much as I am. "But we should stop for a moment," you tell her as you **** yourself to sit up, gently disengaging her hand from around your shaft.

"What?! Why?" Joan asks, looking up at you in worry. "What's wrong, John? Why do you want me to stop?"