Getting Ready
It was a cold winter night within the city of Canterlot. Snow was falling heavily upon the white marble streets. A towering castle loomed over the city. You, the human, were situated within this castle. You lay upon a huge queen size bed without the need of a blanket despite the fact it was winter. For you lay between two huge equines in your birthday suit. The warmth of their large bodies radiated great heat. They were no other than Princess Celestia and Princess Luna.
Their soft, warm bodies were pressed against you. Their fluffy chests were more than enough to keep you warm. Just when you were about to drift off to sleep you heard Celestia speaking to you softly. “Anon, there is something very important that we need to discuss with you.”
“What is it?” you asked.
You then heard Luna speak. “Your life hangs in the balance, our little human.”
“How is my life hanging in the balance?”
Celestia spoke softly. “My dear sweet little human, you are mortal, while the both of us are immortal alicorns. We have found a way to make you immortal. But, we are not sure whether you will like it or not.”
“Does it involve killing somepony and sucking out their soul?” you asked.
“No. Nothing grim like that. You're still not going to like it regardless.” said Celestia.
“What could I possibly not like if it doesn't involve anything grim?” you asked, rubbing your chin curiously.
Without a word, Celestia and Luna made to stand up on the bed. From their standing position they were even more pronounced in size. They seemed like draught horses if anything. Celestia and Luna stood about 21 hands high and about 10 feet in girth. Which made them essentially about the size of a shire horse, but on steroids. Celestia is about 6 hands higher than Luna however. In other words, Luna was 7 feet tall, while Celestia was 9 feet tall.
You then heard a familiar humming sound, you knew that sound to be their horns’ magic. There then came a flash of light, and a massive horse cock appeared each between their legs. Their mighty penises also came with a set of grapefruit sized balls. Their cocks stood about 25 inches long, and were about 7 inches thick.
“Oh.” you simply said, looking on in horror. “Wouldn't those massive penises of yours rip me in half?”
“No my sweet little human. You will be safe. Our magic will protect you even as we stuff our massive penises up your butt and down your throat.” said Celestia softly.
“I-I… I’m not so……” you began, before being interrupted.
“Anon, please, it is the only way,” spoke Celestia in an imploring tone. “We need to cum inside your butt in order to give you immortality. I promise, you will get to mount my backside in return after we're done mounting you.”
You then heard Luna chime in with her voice speaking in a pleading tone. “Please, our little human. We love you. We don’t wish to see thou pass into the void.”
The sound of their imploring voices was all that you needed. “Yes. I don’t want to cause the both of you heartache. I agree to having your massive penises have their way with me. I may scream, I may cry, and feel like a lesser manly man and feel a little homosexual, but I know it will be worth it.”
“That’s not true, my little human. If anything it makes you even more manly and less gay in my view,”” said Celestia.
“Ridiculous!” boomed Luna. “You have proven yourself to be a true manly, heterosexual man by agreeing to be mounted by our massive penises. Nothing could be further from being a homosexual.” she said, while swinging her massive penis from side to side.
You looked on in horror, with your jaw dropped as Luna's massive balls slapped against each other with loud slapping sounds of flesh slapping against flesh. You gulped in fear. However, like a true chad male, you soon stood up on your two feet and approached Luna’s fat ballsack between her hind legs.
Once close, you were bombarded by the scent of her bitter, salty musk as you stood beneath her bloated testicles. Tentatively, you began to lick the midsection upon the underside of her ballsack. This action elicited happy neighs and moans from her. Her huge, black cock bobbed up and down excitedly as you licked her ball-flesh. You could not help but moan at the taste of her. Her balls tasted salty and musky, but also had a faint taste of sweet blueberry to them. You applied lick, after lick upon her testicles, making them sheen with your saliva.
Suddenly, you heard a strange humming sound. This was followed by an azure glow being wrapped around Luna’s cock. You saw the thick veins along her cock pulse erratically as her cock began to slowly inch outward in growth.
Her mere 25 inch cock became a distant memory as her penis gained about an inch by each passing second. You looked to the side, to see Celestia’s cock was also growing in size, as it lay wrapped in a golden glow of magic. You fell to your knees and leaned down upon the floor in worship of their mighty growing horse cocks, and you silently prayed for divine mercy.
Longer and longer, bigger and bigger their cocks became over you. You drooled at the sight of the growing horse cocks. You paid homage to the mighty god horse cocks by masturbating with your small, inferior human penis before the glory of their great and terrible mighty penises.
“Yes, our little human! Worship us with your small inferior penis! Puny mortal!” boomed Luna in the Royal Canterlot Voice.
Celestia protested. “Luna, that’s not very nice. Anon’s penis is cute and sexy!”
“Fear not! I also think Anon’s penis is cute and sexy!”
Finally, the two alicorn’s penises stopped growing inside. Their penises stood at least 50 inches long, and 15 inches thick. Supported by a set of massive watermelon sized balls. You stared wide eyed in horror at this turn of events.
“Our penises have been doubled!” boomed Luna.
“Hehe. Indeed they have.” said Celestia giggling with a hoof over her mouth.
You prayed that you will live to tell the day after all is said and done.