Show her how boys masturbate.
From Create Your Own Story
"Well I can show you how I masturbate," you offer.
"Okay!" Jess happily agrees, ignoring her towel for now.
"Come around here." You guide Jess between your legs until she's standing in front of your erect cock. You make sure to angle your chair so that Julie can still watch.
"Boys are pretty easy. We just go up and down like this."
You close a hand around your dick and pump it slowly. Jess seems mesmerized by the movement of your foreskin and the simplicity of everything. After a minute of studying she looks up at you with a pleading gaze.
"Can I try?"
You nod with a grin and let go of your member. She locks her small fingers around your cock. They're so soft and delicate. She can't even wrap her fingers all the way around your shaft so she quickly adds a second hand above the first. Now in position she awkwardly lifts her hands up and down. Her motions are jerky but her grip is fantastic.
You throw your head back and sigh. As Jess's motions become fluid and faster you think to yourself what a perfect night this is turning into.
"Am I doing it right?"
You look back down at Jess. She's slowed her pace now, less certain than she was a minute ago. Perhaps she thought you were uncomfortable or bored or something when you sighed.
"You're doing great! Did you... want to keep going?" You really want her to but you don't want to push her.
She looks down at the dick she's still grasping. She lowers her hands all the way to the base of your shaft, stretching your foreskin all the way down and forcing your dick to strain against her grip, as hard as you've ever been.
"It is kind of fun. Maybe later!"
Jess releases her grip and grabs her towel, a smile on her face from ear to ear as she wraps herself up again. You breath deeply, already looking forward to that maybe.
"Here's an idea. How about I get Julie to show you how girls masturbate?"
"Oh! Okay!" Jess exclaims, bounding into your lap. You're careful to push your dick down before she lands. The last thing you need is a broken penis. Of course now she's sitting down its length, her thin towel doing little to prevent it from parting her ass cheeks. This is the best and worst torture possible.