Family Ties/Tell Jess to go away.
From Create Your Own Story
You're not really interested in Jessie. You're looking for cock, not pussy. But besides that you don't think that Jess really wants to see what you're thinking about doing to your son.
"Head on back sweetie. Jacob and I are... busy."
Jess pouts and scrunches up her face. "But I wanna watch!"
Your jaw drops in surprise. Is your little Jessie interested in sex already? Inappropriate thoughts flash through your mind, a microcosm of perversion and debauchery. The thought of defiling your son was already getting you wet, but both Jacob and Jess? Goosebumps send anticipatory shivers across your skin.
"Really? Umm... I don't know if you're old enough honey," you admit, still trying to act as a considerate mother.
Jess takes a few steps toward you, a pleading look in her eye. "Pleeeease mommy?" She whines as she continues to steal glances of your exposed tits.
You raise an eyebrow and look toward Jacob. "What do you think, Jakey? Do you mind if your little sis joins us?"
A stupefied grin adorns Jacob's face but he tries to maintain his composure. He's just as surprised as you but perhaps even more interested. "Uhhh... I guess."
"Well as long as your brother says it's okay..." you declare, making this a true family decision.