(I am incredibly grateful for the support and love on the first post of the AU! I'm so happy you liked it, and I hope this second part resonates with you just as much. If there are 20 reposts of this, maybe I'll bring the third part and post it on Ao3! Thank you from the bottom of my heart, and feel free to share your thoughts! 💖)
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The God and the Monster
Poseidon felt the weight of guilt on his shoulders. The sacred oath of the Big Three had been broken once again, and he knew there would be consequences. There always were. But the truth, plain and simple, was that he did not regret it.
Sally Jackson was an extraordinary woman. Strong, determined, full of life in a way that had been erased from most mortals over the centuries. It had been a long time since Poseidon had met someone like her—and he couldn’t force himself to regret loving her. Nor for getting her pregnant.
What tormented him wasn’t the act itself, but fate. What would happen to the child he had fathered? A hero’s life was never easy. And, as much as Poseidon was a god, an emperor, an immortal and indestructible being, he was still a father. And he feared for the future of his youngest.
So, he remained alert. Vigilant. Silent in his own anxiety, trying to keep calm, hiding any trace of having committed this transgression. He didn’t want anyone to notice. He didn’t want the gods to turn against his son.
It was as if the ocean shattered within him. A deep impact, impossible to ignore, reverberating through the very core of his being. Poseidon had felt this before, in ancient times, when a great spirit was about to be reborn in the mortal world. But this time… this time it was different.
For a moment, he didn’t understand. There was confusion—an echo, broken between past and present, as if a dark whirlwind spun through his soul, pulling old memories to the surface. The sea inside him roared, impatient, feeling the dissonance in the thread of his son’s life.
He sought to recognize the soul of his heir, expecting to find a new spirit, free from past marks. But all he found was an abyss of old memories, of battles and betrayals, of a name buried in time.
The revelation hit him like a destructive wave. His son—his youngest, his little prince of the sea—was not just a new life. He was an ancient shadow. A reincarnation.
The one who had defied the gods, who spat on the mercy of Olympus and returned from death covered in blood and lies. The man Poseidon had personally cursed, the one he swore to make suffer, the one who should never have come back.
Poseidon's chest tightened. Chaos spread within him, a whirlwind of emotions impossible to contain. Anger. Horror. Despair. How dare they? How dare the Fates have the audacity to bring this soul back through him? How could Styx condemn him in this way?
His body reacted before his mind even could. The invisible sea currents around him stirred, the salty mist swirling in a violent dance. The sea inside him screamed, a storm trying to break through his mortal form. His primal instinct screamed to end the threat before it was too late.
But then, an image appeared in his mind.
She had no idea. She didn’t know the history her son carried. She didn’t know that the baby she held in her arms had cursed the gods in another life. That he had been a king, that he had been a soldier, that he had been a strategist so cunning that even Olympus couldn’t stop him.
She saw only her son. Her little Perseus.
What if he was wrong? What if, in trying to prevent the monster from being reborn, he tore away from Sally not just her son but her soul? Poseidon knew: destroying that child wouldn’t just punish Odysseus — it would break the heart of the woman he loved. And that thought hurt more than any curse from Olympus.
Poseidon closed his eyes, feeling the sea inside him still roaring. But now, it wasn’t just anger — it was fear. A deep, crushing fear, because he knew what this meant. That boy would grow up. One day, he would remember. And Odysseus always found a way. The ocean outside, once an untamable force, now lay still, reflecting the father — wild, but, for a rare moment, at peace. Each wave seemed to echo the silenced storm within him, a reflection of what he had become.
A distant thunder rumbled in his mind, a reflection of the war waged within him.
For a moment, he almost gave in to the darkest impulse — to end the threat before it could blossom. But then, something fiercely protective grew within him, a wave that swept away his hesitation.
Because that child was his too.
Not just the shadow of a monster, but the blood of Poseidon, an heir of the sea.
And no one — not even the ghost of Odysseus — would dare take that from him.
When Poseidon opened his eyes, it wasn’t just fury. There was a raw possession, a wild and violent love, like a crushing tide.
If Odysseus wanted to exist again, he would have to do it under the waves of his father.
And this time, the sea would not let him escape.
Poseidon didn’t wait a week. Not even three days. The torment inside him wouldn’t allow it.
Time felt like poison coursing through his veins, a salty pulse driving him forward. Each hour spent away from that child was a rising tide in his chest, a current that threatened to drag him to the depths of his own chaos. He needed to see. He needed confirmation. He needed to act.
When he finally appeared, there was no sound. Just salty mist and a damp breeze that filled the small mortal apartment. The moonlight spilled through the window, bathing the crib in silver clarity. The air was too dry, the space too small, and everything smelled of humanity and solid ground — an insult to what he was.
But there, right there, lay his answer.
The baby slept. Curled up, breathing softly, oblivious to the god who now watched him. Poseidon stood still, every muscle rigid, his gaze fixed on that tiny, helpless form. And inside him, something ancient and fierce roared.
He knew what he should do.
If it were true — if that tainted soul had returned — he would end it. Right there. Now. He would kill the child and give Sally another. It wouldn’t be the first time a god had shaped such a destiny. It wouldn’t be the last.
Or at least, that’s what he tried to convince himself.
But the sea… the sea is not made to kill its children.
Poseidon felt the conflict scrape at his insides like a whirlpool. His feral instincts were at war — the primal urge to destroy a threat collided with something even older: the wild, possessive instinct to protect his offspring.
Because the children of the sea were rare.
The ocean, by its nature, was not kind. Infant mortality among the sea peoples was cruelly high. The waters claimed their young with the same ease with which they created monsters. And so, those who survived were precious. Touched by the sea, shaped by it, they were part of the ocean’s soul. And any mother or father who dared to harm a child… well, the ocean itself would crush them.
And Poseidon was the sea.
His fists clenched, and he growled low, a guttural, hoarse sound like a wave breaking in the distance. The idea of destroying something of his… something that carried his essence… wounded his very nature. But what if that thing was him? What if the man he hated — Odysseus, the shadow who had cursed him for so long — was there, reborn in his blood?
A delicate sound, almost a sigh. He looked at the cradle.
Two eyes were staring at him.
The world seemed to tilt.
The irises were the color of the sea — his color. But the shape… the shape was hers. Sally. They were gentle, wide, innocent.
Poseidon held his breath.
It was a small, pure sound. A carefree giggle that exploded like foam on the waves, and Poseidon felt something inside him crack. The storm within him stalled for a brief moment, like a raging sea suddenly becoming smooth under a gentle breeze.
He stepped forward — a shaky step, then another. Powerful hands, capable of destroying cities with a gesture, now hovered over the cradle, uncertain. Then, with a hesitant movement, he took the child into his arms.
Poseidon trembled. He could smell the sea air that surrounded the boy, undeniable proof of his lineage. But there were no fangs. No claws. No scales or gills. Just soft skin, dark hair, and eyes that stared at him as though he were the only being in the universe.
His long fingers traced the baby’s body, instinctively counting and checking.
Ten fingers on hands and feet, all in place.
Poseidon let out a ragged sigh, something between a sob and a hoarse laugh.
“I’m sorry, my pearl…” his voice was just a whisper, almost inaudible, as he held the baby more firmly. “None of what happened was your fault. None of what will happen will be your fault.”
Little Percy smiled at him, babbling something incomprehensible, and Poseidon felt a violent wave of possessiveness rise within him.
That thought hit him like thunder.
“You are not a punishment for me.” Poseidon murmured, his voice thick with emotion. “You are a punishment for him.”
There was a dark flash in his eyes — the cruel irony of it all. Odysseus, the man who had most challenged him, now reborn as the heir of the one he despised most. What more poetic punishment could there be?
Poseidon laughed softly — a bitter sound, but laden with something new. Something dangerous. A wild, raw love, as vast as the ocean.
“Funny, isn’t it?” he whispered to the child. “Perfection born of the greatest offense. The most monstrous man reborn… as my son.”
Percy just yawned, his eyelids beginning to droop, snuggling deeper into the god’s chest.
Poseidon closed his eyes, feeling that tide of emotions drown everything that had once driven him. The unbalanced hunter fell silent. The king-god stayed behind.
Only the father remained.
With the utmost care, he placed Percy back in the cradle, adjusting the blanket around him. His fingers brushed through the soft strands of the baby's hair.
"Nothing will ever be your fault. And I will always be proud of you." His voice was a promise, sealed by the ocean itself.
A final kiss on the forehead.
And when Poseidon left that night, the sea became calm.
In the following months, the weather remained perfect.
