Holy Shit

His mouth drops open at the sight. On the couch Karen lays back naked, her big tits bouncing as her best friend Katie fervently grinds her pussy against his sister's thigh. Katie's thick ass and thighs bounce with every thrust and, even though he can't see it, her arm moves in a way that he knows she's fingering Karen just as emphatically as she is grinding against her.

Frozen in place, he stares, unsure how to react to the scene until Karen's face turns and sees him. Her eyes grow wide with fright as she reaches up to push Katie off of her.

"Oh my god! Katie stop. Oh my god. Brett, what are you doing home? OW!"

Katie's legs clamp down around Karen's thigh, shaking and arching her back, as an orgasm washes over her. "Fuuuuuuuuuck...", she moans out as her whole body shakes, cumming harder than Brett has ever seen a woman do before.

Both Brett and Karen can only watch as she rides out the orgasm until her body falls limply against his sister's chest. With a flushed face, she sheepishly apologizes, "Sorry, I couldn't stop it."

Pushing her off and onto the couch Karen stands up, trying to cover both her tits and her crotch. It's a futile effort, her breasts spill up and over the arm crossed over them. "Brett, you saw nothing. Do you understand? We were just... we were... Shit."

Brett already knows he'll never forget what just happened, or the unexpected reaction he's feeling. He wishes he'd seen more, seen his sister cum just as hard and uncontrollably, even wishing that he'd been able to join in. "Yeah, I don't think I do."

"What do you mean? You don't understand?" She stands there, looking back and forth, confused at the unexpected reply. "Brett, I need you to forget about this."

Finally starting to come around Katie chimes in, "Yeah, I doubt that's going to happen." She starts making a jerking motion with her hand, "You know what he's going to do tonight thinking about what he just saw."

"You've got to be kidding me!" Karen's exasperated statement comes as she turns and begins to walk away.

Katie smirks, catching him staring at his sister's swaying ass as she walks up the stairs. "It's pretty amazing isn't it?"

"What?" Brett asks with a face quickly flushing from embarrassment.

Scooting up and leaning back against the arm of the couch Katie repeats herself, "It's pretty amazing. Her ass that is.", she elaborates a little to make sure he understands.

Still ashamed of himself, he murmurs his response, "Yeah, it is."

"Brett?"

Breaking his gaze, fixated on the stairway Karen had disappeared up, he turns to look at her. Her hands have moved up to her tits, almost as large as his sister's, and spread her legs to show off her clean shaven pussy.

A hand starts making its way down between her thighs, parting her wet pussy lips. "I see what you've got there." Nodding down, to his crotch, making him realize the physical effects of the scene were clearly visible. "Can I help you with that?"

Massive tits, thick ass, always covered by clothing that hugs her body showing off all of her curves, of course he's imagined fucking Karen's best friend before. He never imagined he would have the opportunity though. Now that he does, he pauses, but only for a moment before stripping his shirt up over his head and crossing the living room to the couch.

Stopping in front of her, he undoes his belt and starts shoving his pants to the floor. As they come down just past his thighs, and his cock pops up into view, she reaches out to wrap her hand around it. Running her thumb along the underside of his head, gathering the precum already leaking, and then using it to allow her hand to slide smoothly back and forth.

Sliding her hand down to the base, she leans in, opening her mouth, and takes him in. The position of her body on the couch prevents her lips from going far so she makes up for it with her tongue. It alternates between rolling in a wave against the underside of his cock and circling around the head. Her hand gets back to work, stroking what she can't get into her mouth. She bobs her head, pulling back until just the very tip is left pressed between her lips, then back forward again to engulf the head.

He's had his head tilted back, eyes closed, almost overwhelmed by the sensation of her lips wrapped around him. Adjusted now, his eyes open to look down at the top of her bobbing head, it's curly blond hair covers half of her face and he wraps it up in his hand to make sure it doesn't get in her way. They wander down to her large breasts, then follow her arm down to where her hand is still tucked between her thighs. Its fingers still spread her lips allowing her juices to visibly run down and soak into the couch cushion.

The need for more builds, overwhelming him to the point where he roughly grabs her wrist and tugs her head back from his cock by her hair. "That's enough of that.", he orders before releasing his grip only to then grip her by her ankles. Too impatient to allow her to move on her own, he twists her around so her ass is at the edge of the couch and pushes her legs up in the air.

"Oh yes." She whispers wither her legs in the air, almost folded over, and then held there by his weight as he leans in. Spread wide, dripping wet from her previous orgasm, as well as the blow job, he slides right into her. He takes a moment, to enjoy the feeling of his balls pressed up against her upturned ass. The moment passes, the impatience taking back over and he moves one arm behind her neck, the other on the couch to keep himself from collapsing into her as he begins to fuck her.

He pulls her in closer to him, using her body to fuck him back. "Yes, use me." She repeats it over and over again as her hand moves down to rub her clit. His eyes stayed glued to her tits, jiggling and bouncing with each of his thrusts down into her. Suddenly she goes quiet, her mouth hanging open, before letting out a groan. "Right there. Keep hitting me right there..."

The walls of her pussy tighten around his cock, clamping down firmly, almost pinning him inside. For seconds it stays that way her whole body tense, until her hands grab onto his arms, digging their nails in. The tension in all of her muscles come and go in waves, each contraction pulling her body up off the couch before releasing, allowing her to settle back.

Watching her lose control pushes him over the edge. Pulling out he strokes his cock as he starts to cum. Still in the midst of her orgasm with her eyes closed tight and quivering, shots of his cum land against her body. Each one going further than the first, leaving her coated from her stomach to her chin.

"Wow," startled at the sound of his sister's voice behind him, he whips his head around. "Impressive Brett. You too Katie." Now clothed, she stands there with her hand on her hip, shaking her head, taking in the scene.

Any shame he had at the beginning is now gone. Turning around to face her he stands a little straighter than usual to make sure she can clearly see his cock. "Shit, when did you get here?" Whether it was from interest or the way it hung there, still wet from Katie's sopping pussy, and it's last dribbles of cum dripping to the floor, her eyes flick down to it.

"Oh," Katie chimes in, "she's been there for a while." They both look over at her, cleaning herself by scooping up his cum and sucking it off her fingers. "She even had her hand down her pants for some of it." she says giggling.

Karen does, in fact, seem to have a wet spot on her leggings right at her crotch. "Well, um...", she starts and then quickly leaves the room again.

Plopping down next to Katie, he leans back, and sighs.

Her hand snakes over to play with his softening cock. "We should totally do this again, what do you think?"

"Yeah, definitely." he replies and then just barely loud enough to be heard, "But, how do I fuck my sister?"

Katie giggles, "I'll help with that."