Fiona has some pre-dinner 'fun'

After feeling up Allison for a while, Fiona shoots you a grin, then steps directly behind Allison, encircling her with both arms. "Are you sure you wanna introduce this girl to mom, Jesse? Just look at her - " Fiona abruptly lifts up the front of Allison's miniskirt with one hand, displaying her bare pussy.

"- She's running around in a miniskirt and no underwear!" You - and Elsie - stare at Allison's bare snatch...it's almost hard to believe she worked up the nerve to go outside like that. Fiona reaches down with her other hand and uses two fingers, stroking the length of her slit. Allison bites her lip to suppress a moan, flushing red in embarrassment, but not resisting at all.

"...And she's soaking wet!" Grinning while acting 'outraged', Fiona lifts her hand up, showing off her fingers, which glisten with Allison's proof of arousal. After showing them off for a bit, Fiona wipes her fingers off on Allison's face, leaving her cheek with a wet, shiny trail of pussy juices. You feel your cock throbbing intently as you stare, transfixed at Allison being felt up and humiliated by your sister.

"Are you trying to leak all over the floor? Do you want the carpet to smell like your cunt? Apologize!" Fiona gleefully hisses into Allison's hear loud enough for you to hear, then demands she apologize. "...sorry..." Still looking humiliated and cowed - but also aroused - Allison meekly apologizes immediately.

Apparently not satisfied, Fiona's hand darts down again, landing a quick, but sharp-sounding slap on Allison's pussy. "You're still leaking whore-juice though!" Allison involuntarily lets out a distinctly aroused-sounding moan, leaning forwards as if her knees are buckling a little. "S-sorry!" She apologizes again, her voice breathy and her eyes looking glassy with arousal...

"If you're sorry...why are you still soaking wet?" Fiona's hand slips back between Allison's legs, her fingers slipping easily into your girlfriend's snatch. Allison's attempt at a reply cuts off into a moan as Fiona forcefully fingers her, and from the lustful expression on your sister's face, you can tell she's thinking about pulling her cock out and fucking Allison right here, damning all the consequences.

A moment later though, you hear your mother heading into the room from the kitchen, clearly coming to meet Allison for the first time.