Absolutely that would be impolite

You say, “Anyone home? It’s a little chilly out here, sis.”

She laughs and says, “The door is unlocked already, bro. C’mon inside, but don’t rush in too quickly.” She felt the head of your dick poke itself through the entrance of her asshole. “ohh fuckk…nice and easy, bro. This is my first time with anal…”

Something about that only made your dick even harder as you gently gyrated your hips back and forth to slowly creep inside. She was making guttural sounds of pleasure like a beast in heat as you dick crept slowly more and more inside of her tight asshole. You grabbed her ass cheeks firmly as you spread them apart to give yourself as much space as possible. You were amazed as how her asshole was now sucking you in and felt that your dick was completely engulfed. You began to thrust ever so gently as she let out a loud moan.

“Oh fuck me!” She cried out as you were just gently pulling your dick out and gliding into another gentle thrust had caused such a sexy reaction. You continued to pick up the pace as you grunted with just how tight her asshole was and she was moaning quite loud. “You can go bit faster, bro…uhhh…” was all she could say as you picked up the pace. You weren’t going to last long as you felt yourself getting close to cumming but she was indicating she was just as close herself.

“I’m…uhhh…about to cum…sis,” is all you can say through your grunts. She continues to moan and simply nods as she is lost in the pleasure of this new feeling.

You thrust one last time as far in as she lets out a sharp moan into a prolonged “fuuuuuck….yeeees…” as your hot semen fills her virgin asshole. You feel yourself shrinking rather quickly since the cool water is working well. You use what little strength you have to get the both of you back to the steps. Her asshole finally releases you as you put her down on the step next to you.

She lays into your shoulder and says, “That was incredible, bro. You took my ass virginity.” You both chuckle as she continues to say, “It’s a bit cold now. Let’s dry off and head back inside. She got out of the pool first as you watched her ass rise out of the water. “Wait a second…” she said as she ran to the lawn and squatted. You watched as she pushed the semen out of her asshole as said, “Fuck, bro! That’s a lot of semen.” You both chuckle as she unloads the semen as best as she can. You head to the box full of towels and have a wonderful idea instead.

You watch as your sister cleans out the semen out of her asshole as best as she can and say “How about we air dry instead of toweling off? Less laundry for mom to have to do.”

She got up and gave me a kiss saying, “That’s a wonderful idea, bro.” She was holding your dick that was already regrowing back to its erect state. She led you to the lounge chairs with a firm grip on your hardened cock.