It wasn’t fair! Nullable was 18, and ready to become alpha! Yet his father still rejected him, for what reason?! He has all the traits of an alpha: a huge cock, big balls and a restless libido to keep breeding bitches forever. He sighed angrily and sulked to the floor as he walked through the forest. Then, he saw a feral bird… A beautiful lady bird by the looks, with a striking blue plumage of feathers. He smirked… Maybe this is what he needs, he thought, as he picked up the bird and fingered it’s small cunt - angling it to his still-erect cock. 
“Yeah… I need a bitch. My dad needs to see how I fuck!”
All the goat could care about was fucking this sexy feral bird without care of it’s wellbeing - he was really, really horned up and all he could think about was a hole. He is 18, after all - and with it, comes the desire to fuck anyone and anything. With his dick throbbing over her small cunt, he pierced through the tight entrance and his cock entered a realm of bliss - the cunt stretching out to accommodate his huge piece of meat that was forcing it open and making the bird scream in pain.  
With the adrenaline overtaking him, he took hold of her wings and used them as a handle for her cunt to slide up and down on his superior, needy cock.
“Maybe this’ll show dad that I can be the alpha!” He shouted, with drool hanging out of his mouth and dripping down to the bird’s fur below. 
His cock throbbed bountiless amounts of precum inside his stretched out cunt, and it provided the perfect fucking lube for him to continue thrusting inside and out without a care in the world, properly stretching that cunt out to accommodate his thick young alpha cock. His big black balls whacked against the bird’s behind again and again, his moans of pleasure overpowering her screams - his whole world collapsed into pleasure around him, hearing nothing but a juicy cunt fuck and the slapping of his balls against the warm fur.  
He was a little scared when he heard his dad’s voice, thinking that he may have caught him in the act and was ready to beat him up for fucking a feral animal in the wild - but the response was quite the opposite. In fact, his big hunky goat father was right in front of him now - stroking his big thick fatherly cock while watching his son feverishly fuck a bird.
“Fuck that cunt, son. Show me how bitches like that should be used.”
He was no longer ashamed, and ready to go all in - continuning on his fuck with the same amount of energy and lust, hearing his father jack off his precum-covered cock with his deep moans. He could hear his father get close to him, his deep huffs of pleasure overpowering his moans. 
“Birds are the perfect little fleshlights, ain’t they - kid?”  He said, as he lined up his cock to the bird’s screeching mouth, then moaning out deeply as all the saliva covered his cock and he slowly shoved his thick shaft inside the whimpering beak of the bird.
Nullble stopped his diabolic rape for a moment to admire his 50 year old father sliding into the bird’s beak, his cock hard and balls full.
“I was so virile in my youth, just like you,” he continued, then pointed at Nullble’s cock inside the cunt which had some blood trickling down the edges.
“I was so mad that my father kept berating me for not finding a mate, I’m sorry son. But fuck, I never thought you’d be an animal fucker just like ‘yer old chap.”
Nullble continued thrusting and throbbing his cock inside the now-bloody cunt as his father kept talking, giving him just the words he needed.
“You know, you fuck like a god. You got your daddy so worked up, just seeing your thick cock go into her tight bird cunt. Fuck, her mouth feels so good…”
Once his thick cock bottomed out in her throat, the father moaned out and looked lovingly at his face, caressing his face with an evil smile.
“Heh, I guess it runs in the family. We’re both pervs.”
Nullble was already sent way over the edge by his father joining him and feeling his cock brush against his own in her crushed insides, so he just had to finish her off now.
“Finish her, son. Destroy her insides with your thick alpha cock, youth.”
With a loud roar, Nullble finally got to show his more alpha and dominant side by fucking this animal bloody. He loved the feeling of destroying her insides with his huge cock, the way his father dirty talked him more and more as he fucked into her destroyed cunt - it all became too much to bear. The bird was pretty much reduced to a hollow fleshlight on the teen’s throbbing cock, long since dead from the lack of air due to the father’s cock plugging up its throat. Now all that remained was to fill it with thick spunk.
His father was on the edge of orgasm too, taking in the pure sight of pleasure as his son used that bird up and down like a fleshlight on his cock - he was jacking off in front of his son, stopping his throat fuck to give his son the bird to himself, then parting his son’s lips - ready to blow his thick load inside his son’s mouth.
“Do it, son. Fill ‘er up good! Destroy her cunt with your huge cock and give her all that virile young cum she craves!”
With a final cry and victorious thrust, Nullble’s cock went all the way through the bird - pouring his huge load of cum through her mouth, leaving nothing but a thick gooey red/white gooey mess on the floor as his big balls churned on and on, shoving more baby-batter inside her until the bird was inflated and full - and the mixture of cum and blood started leaking around his cock. 
He barely even registered that his father had blown his load inside his mouth until he felt the huge puddle of sperm that he had to swallow. And swallow he did, for that is his father’s sperm, alpha sperm that he’ll need to drink up if he wants to become the best in the tribe.
“Hah… Hah… I think you’ve shown why you can be alpha, son,” said the dad with a telling smirk on his face. Then Nullble blacked out from the amazing fuck he just had, the bird still lodged on his cock. What he didn’t know, however, is that during his sleep - his father dislodged the corpse from his cock to fuck it next to his son all night, filling it with even more alpha sperm - but this time from the loins of a 50 year old muscular goat.
That was the story of how Nullable became alpha!