The Hominin Exhibit

Note: All characters are over age 18! The author does not endorse imprisoning siblings in an alien zoo and exposing them to pheromones.

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The worst thing was, she wasn't even sure if their captors needed the pheromone gas anymore.

It had become impossible to deny that Sarah and Kev were quite trained. By now, they knew the zoo's schedule instinctively. They expected it, they almost...looked forward to it.

Okay, not just almost.

Certainly, Sarah could easily see her brother's anatomy rise to meet the next tour group well before any chemical change inside the impenetrable glassy-walled enclosure.

But there was a similar change she had observed within herself. She couldn't help it.

There were 3 tours per day, every day that the zoo was open. At T-minus 10 minutes before each tour, her thighs dripped, her body flushed with Pavlovian anticipation, well before the puff of what she and Kev had been calling "pheromone gas" that would push her libido into overdrive.

If they were even still bothering to deploy the gas. For all she knew, it had been replaced with a placebo.

By the time the tour gathered to watch and ooh and ahh, she would already be in Kev's arms, huddled among the sad little fake trees and boulders, the tiny pond, and, most bafflingly, the rock-hard replica of a Reebok sneaker.

His hands would comfort her, his lips whispering some of the gentle brotherly nonsense that the two of them used to keep sane, to remember who they were, who they had been.

At first, rebelliously, they had attempted to make their sex mechanical, boring, minimal. Just enough thrusting and rubbing to get each of them off and waft away the cloud of pharmaceutically overcharged horniness.

Later, they had tried to make it fun. Wacky. Obnoxious. They had experimented, giggling as they tried every outlandish position and method they could think of, joking about trying to spread inaccurate and bizarre ideas about human sexuality across the galaxy.

Eventually, they had gotten bored with their own antics. They had stopped giving a crap about making fools of a bunch of aliens. The only thing left that was important to her, she had realized, was her brother. The love they shared.

The love-making they shared, too.

When they had first been stuck in here, merely seeing him naked had been shocking. To be naked in front of him, humiliating. To come out of the induced haze of sexual frenzy, and remember the way she had moaned for the camera-toting spectators as he plowed his cock into her -- mortifying beyond description.

Now, she could almost set her shame aside. She could even find room for pride, at the way she could turn him to jelly, bobbing her head on his cock, or finding just the right rhythm when she straddled his hips.

Now, she could think with fond appreciation of the way he had of wrapping his lips around her clit while his fingers filled her. Or the way he shyly tweaked and tugged her nipples when he kissed her, when the gas was beginning to take him.

Although, lately, she'd had to ask him to take it easy on her poor boobs, now becoming swollen and sensitive in sync with her growing belly.

He wasn't always able to restrain himself.

The effect of the gas seemed to be inconsistent. Perhaps they were being dosed differently at different times, in some incomprehensible pattern. Or perhaps it had to do with hormones. Or simply their souls, banging against the walls of the cage.

Sometimes, their fucking became wild, desperate. There were days when she would wrestle him to the ground in a red haze, rocking her cunt against his face with her full weight, ignoring his discomfort as she ground him into the fake dirt.

Was she was just too affected by the gas to care? Or, the most shameful thought of all, was she was taking out her frustrations on her brother, the only person she could hurt?

He gave as good as he got, she had to admit. There were days when he would grow impatient with her lips teasing his cock. When he would suddenly grasp her head in his hands and fuck her mouth, heedless of her gagging sounds as he filled her throat mercilessly.

He always looked so stricken when he apologized afterwards. But the worst thing about those times he left her coughing and spluttering was that they were beginning to invade her fantasies.

Maybe it was the idea that it was something he needed, deep down. And if her brother needed it, she needed it.

Or perhaps, more disturbingly, it was something she needed, deep down.

Now, when a tour was approaching and she felt her cunt growing excited, she sometimes imagined that this would be one of those times. When he would overpower her, let his urges run wild, use her like a fuckdoll.

These were not the sort of fantasies you could tell your brother about. But, maybe it was time she got over that. Maybe she could lift some of the pain from behind his shining eyes. If she could do that, it would be worth any indignity on her part.

It seemed they were going to be in here together for a long time.