Keep watching

You peek in again. It seems that the older sister is too distracted with fucking Stacey to come after you. They're still snogging each other, drooling so much that it drips from both of their chins.

Stacey suddenly yelps as she's thrown off and flipped over. The older sisters rips off her clothes into shreds, and stares at her sisters completely naked body. With such contrasting body shapes you can hardly believe they're sisters.

"Sis', are ya' still in there?" Stacey asks.

"Sissssterrr... I looooveeee sissssterrr... I... I want to... fuuuuckkkk sissssterrrr..."

Stacey looks at her with tears in her eyes. "I love ya' too sis'. I'm so glad yer safe now. I wanna' be with ya' forever..."

"Fooorrreverrr... fuuuuck fooorrreverrr..."

"That's... that's right. Soon I'll be like you an' we can be together forever."

The older sister is now the one on top, and her hairy yet prim snatch hovers over Stacey's surprisingly smooth one. She lowers it so that they touch and kiss, and she begins to rock her hips, grinding them together. They squelch loudly, the noise hanging in the air along with their moans and grunts of desire. Stacey grabs at her sisters tits, which are no longer flat, but delectably rounded. Not nearly as big as her own, and honestly, not any bigger than average, but it's still something. The older sister bucks and writhes as her nipples are played with, not used to having much sensetivity in them. She orgasms, loudly shouting a battle cry as if it were her first; in a way it is her first, her first in her new life. You hope it's one she'll never forget. She pauses, but then gets right back to grinding, shifting her body so that Stacey's leg is over her shoulder. The sofa's upholstery is a wet mess, and you doubt anyone would be able to get the stain of their juices out. Not that anyone would want to. You can smell it from outside, and you'd be lying if you said it didn't smell divine and sexy and... good.

Stacey scrunches up her face, as if from pain but you know it's pleasure, and moans breathlessly as her hips suddenly spasm, and she orgasms. It's cute, totally different from what you were expecting; she's like a purring kitten.

Her sister, sensing that they should rest for a little bit, climbs off and gets her knees on the floor. She begins to lick her sisters pussy clean, her hands playing with herself in the meantime. Stacey sighs, leaning back in her seat. She mindlessly lifts one of her own breasts and takes a suckle from her own teat. Her eyes suddenly go wide as she spots you looking through the window, and she almost chokes on her own milk.

"WAIT WAIT WAIT, THERE WAS A WANKER WATCHIN' US THE WHOLE TIME?!" She looks mad. Very mad.

"Heeee cuuuuute..."

"YA' KNEW?!" She pushes her sister away and stands on her own two feet. "THIS WAS A PRIVATE FAMILY AFFAIR! I'M GONNA' TEAR 'IM A NEW ONE!"

Uh-oh, best to make yourself scarce.