The First Assfuck

Who were the first two men to decide that an asshole or mouth would be a great place to stuff a hard cock? I'm sure there's no way to really know, buy I'm sure it happened a long time ago. I imagine a couple of cavemen out on the hunt. They're miles from home with a fresh beast in a heap at their feet. they start a fire and roast up some saber-toothed tiger. they tear into the meat and gorge themselves on the roasted flesh. After they have their fill they lounge around the fire pumping each other's egos up with the heroic stories of the hunt.
As they eat and drink, one decides to take a piss and the campfire illuminates the huge neandertal cock as he flips up his fur loin-cloth. His piss flows out hard and loud, hitting the rocks and ground below and his buddy joins in. They marvel in amazement as they have the first piss sword fight. They notice each others cock and heavy nuts. One of them comments that he has the bigger dick and the other scoffs. He shakes it at him and flips it around in the air, letting his buddy know that it does indeed get much bigger than this... and soon both of their cocks start to inflate. Staring at each others fat cocks, one kneels down to get a closer look. His friend turns to give his friend a better look and his hard meat slaps his buddy in the face. They laugh and as his friends mouth is open wide the other stuffs it in his mouth. he realizes right away that it feels warm and wet, like his woman's pussy. The cocksucking caveman likes the feel of the pumped up meat in his mouth and starts to suck on it. Soon they are taking turns feeding on each others hard caveman cock (first suck-jobs).
It's starting to get cold away from the fire and they make their way back to the warmth. The last one to be on his knees doesn't bother to walk, but just crawls back. As he crawls on all fours back to the fire his friend notices the hole that is positioned in just the same place as his woman's hole is and the proverbial light bulb lights up. He grins and slaps the hole. To his astonishment, he responds just like his woman and his back arches and his hole points way up in the air. His cock is still slick with spit (the first lube) and he thrusts his still hard cock deep into the first man-cunt. It's warm and wet just like a cavewoman hole and he starts thrusting. His friend responds with a grunt and a scream and his man-cunt opens up (the first pig bottom). They continue to hump and thrust next to the warmth of the fire. Their hairy, stinking bodies bulge with muscles as they they moan and grunt in the open moonlight. As the first top feels like he is about to dump his load, he gives his buddy the first reach around and they howl and gasp as jizz starts to fly out of the bottom as his ass gets filled with the thick load. They fall to the ground in a sticky, hairy heap. they know enough to be a little scared that that a baby might actually start to grow in the bottom's ass and then they'd have some explaining to do. But this doesn't happen, so they decide to keep this to themselves (the first closet).
In the future they become the best hunters in the tribe and everyone wonders about their extended hunting trips. But nobody questions them because because they alway return with the meat.