The Deadly Quicksand

"Bobby!" she whined, hugging the towel tighter to her nakedness, "will you stop staring?"

"I can't help it Sis," I lied. "It's your hair."
 "What's wrong with my hair," she said, aghast. She spun around, seeking out the mirror on the wall, inadvertently showing me her bare ass.

"When your hair's all slicked back like that, it makes you look like a movie star."

"Oh," she said, turning around, giving me a sheepish look. At that moment, something clicked between us. It was like all of a sudden we were seeing each other for the first time - no inhibitions, no games - just a man and a woman sharing a primal bond as old as time itself.

Her look of honest innocence turned into a garish laugh. "You scumbag! You never give up, do you?"

I dashed for the bathroom, feeling the snap of her towel against my ass.

When I was done with my shower, like four minutes later, I found her lying on my bed, naked, reading a copy of the Shaklee catalog she'd left at my place months ago. She was curled up on her side, giving me a perfect view of her private woman-parts.

I stared at her puffy cunt lips sticking out from between her legs like two miniature bananas. I marveled at the beautifully sculpted lines of her labia swirling up to her clit like an orchid. I gazed at the twin mounds protecting her moist slit, like puffy pink cushions. I peeked at her puckered anus, all round and symmetrical, with nary a pimple in sight. My cock grew 4 inches in about 20 seconds.

"Hey Bobby," she smiled, setting aside her reading material, "I was thinking, since you saved my life today, I sort of owe you, so I decided you can have your way with me if you want to. But just this once."

"Just this once?" I whined, combining our adversarial brother/sister relationship with the rush of lust that was consuming me like a Southern California forest fire. "Isn't that kind of arbitrary? What if you like it?" 
"Oh, I know I'm going to like it," she purred, easing over on her back and letting her legs fall open. "It's just that I don't want it complicating our lives. It would be too distracting, knowing that anytime I needed some dick, I could just come over here and take my clothes off. I'd never get any homework done."

While she was talking, her right hand was sliding down her tummy, till her fingers were tracing circles around her clit. I dropped my towel, and climbed between her legs.

"We could make a rule that we only do it once a week," I said, as I got down on my elbows and started nibbling at her inner thighs.

"Once a month," she countered, pulling back the hood over her clit.

"How about at least once a month, but not more than once a week?"

"Whatever," she moaned, twitching her cunt in my face. "Just do me, okay?"

******

So that's how it started with Sis and I. Once or twice a month, (which sometimes includes a whole weekend) we get together and have forbidden incestual sex. It feels perfectly natural to us. In fact, we see it as a way to lower our carbon footprint, since, if we weren't scoring with each other, we'd be out driving our cars from one bar to the next, polluting the world with the byproducts of our lust.

This revelation has inspired me to do my thesis on our relationship, calling it 'The Benefits of Utilizing Incest and Casual Sex as a Means to Lower Greenhouse Gas Emissions.' I'm thinking, since my prof is a dirty old man, if I were to included some photos of Sis asleep on my bed, with my cum oozing out or her pussy, he'd probably go for it.

There is still one issue Sis and I need to work out. Are we supposed to recycle our cum? And if so, after I have ejaculated my cum into, or onto my Sis, is it her responsibility to recycle it, or mine? These are ethical questions that will be addressed in my thesis, after exhaustive research, of course.

In the meantime, it feels good to be contributing to the health and well-being of our precious earth, and doing it at the grassroots level, all naked and sweaty. I think if we all just made an effort to open our eyes and look around us, we could find sex partners right under our noses, which would be the perfect way to honor the spirit of Earth Day.