A/N: This is an idea I've been toying with for a while. I started writing this in hopes of dispelling my writer's block on my Supernatural stories, and this was the result. Anyway I couldn't find any that sounded much like this, so I figured I'd give it a shot with my idea.

Disclaimer: All belongs to Rick Riordan, folks. Sadly…

/

Chapter One
Betrayal

For the first time in many hours, it was quiet inside the tiny New York apartment. Outside the night was still and quiet, the faint hum of busy New York streets the only sound disturbing the night.

The sudden wail of a newborn shattered the stillness like a gunshot. With a jolt, the dark-haired woman sat bolt upright and threw off her covers, braving the cold as she hurried towards her son's room. Dark circles marred the skin beneath her eyes, and had ever since bringing her newborn son, Percy, home from the hospital. Her hair was in constant disarray, sticking up in all directions, and she was the most exhausted she had ever been in her life.

"Oh, how I wish you were here," she whispered into the night, thinking of Poseidon as she hurried to his son.

Percy was wailing loudly, waving his arms around as he screwed up his face and screamed for all it was worth.

Sally scooped him up and cradled his tiny form in her arms, making soothing noises as she danced around his room, frantically trying to get the noise to stop. The next-door-neighbors banged loudly on the wall, startling the baby into louder cries.

"Helpful," she muttered, glaring at the wall as she struggled to soothe his tears.

After long minutes of crying, Percy finally started to settle, blinking up at her with sea-green eyes from under his tuft of dark hair.

"You look so much like your daddy," she whispered with a loving smile, tenderly kissing his brow as her tiredness was rapidly forgotten. From the moment her little baby had been born, he'd become the most important person in her entire world. She loved him more than life.

When Percy was finally settled and rapidly getting sleepy, she settled him into his crib with its undersea-themed mattress pad and turned on his fish and seahorse mobile. He made a happy little noise, stretching his hands up towards the animals as he yawned hugely and smacked his lips together. Just like that, his little eyes closed, and seconds later he was asleep.

Sally sighed in relief and sat in the rocking chair, suddenly too exhausted to stand. Fear gnawed in her gut as she remembered one of the last conversations Poseidon had had with her.

"Sally, please," he said softly, his eyes turning stormy as his gentle hands grasped her shoulders. "I cannot protect you both up here. They will come for the baby. Their scent will be strong. They will not be safe up here. Let me take you with me, into the ocean. None will harm you there."

"Poseidon, I don't belong in a palace beneath the sea," she said gently, reaching up to cup his cheek.

His eyes closed, his expression akin to agony. "I cannot stay, love," he told her in a rough voice, squeezing her shoulders just a little tighter. "Zeus and the ancient laws forbid it."

Sally bit back her tears and stepped into him, wrapping her arms around his waist and pressing her face to his chest. He was warm, solid, real. The scent of the sea clung to him, singing to her as she struggled to control the welling emotions in her chest. His arms came around her, holding her tightly to him.

No one had ever made her feel this safe, or this loved.

But she knew with perfect clarity that this — what they had — couldn't last forever. He wasn't hers to keep. He belonged to the sea. No, he was the sea.

Untamable, unpredictable, powerful.

And yet, for all his power, gentle — always gentle.

"I know you can't stay," she whispered brokenly, squeezing him tighter. Gods, she didn't want him to go. She wanted him to stay with her, to see their child born and raise their son or daughter alongside her.

"There is one place," said Poseidon heavily, not pulling away. He tightened his arms when she tried to pull back, desperate to keep her there with him. Just for a little while longer. "One place where our child will be safe," he expanded.

Sally tilted her head so that she could study his profile. He looked solemn, now. "Where?" she whispered.

"A camp for demigods like him," he explained, finally meeting her eyes. "Camp Half-Blood, on Long Island. There he will be safe from monsters hunting him."

"You want me to give up our child?" she demanded angrily, stepping back and away from him.

He kept his hands on her shoulders, staring down at her with utmost seriousness. "No, love," he said gently. "Not permanently. His scent will be unbelievably powerful. He will need training to survive and fight the monsters who will hunt him all his life." He grimaced, looking down at his sandals for a long moment before meeting her eyes again. "I am sorry, my love, for putting the both of you in such danger."

"I'm not giving up our child," she whispered fiercely, tears gathering in her eyes. She left it unsaid that the child would be her only connection to him she had left. "I won't."

Poseidon sighed and nodded. "I understand you want to keep the baby close, Sally. He or she will be your only family." Those eyes turned intense, boring into her, his expression a cross between pain and determination. "Promise me you will at least consider sending our child there for a time each year. I… I want you both to be safe," he said softly. "I cannot protect you up here. I will do what I can, but outside my realm, there will be little I can do. I am forbidden from interfering directly."

"Just as you were forbidden from breaking the oath you and your brothers took on the Styx?" she asked with a watery smile.

He had the grace to look chagrined. "They will call it a mistake, Sally, and in one way perhaps it is. In breaking my oath on the Styx, I have condemned him to a life of hardship. If he is the prophesized child…" he trailed off, shaking his head. "But I do not regret loving you, same as I know I will not regret this child. I, unlike most of my family, actually care for my children."

"I know you do," Sally said, forgetting her anger. Poseidon only wanted to protect them, but she was too stubborn to accept his charity. "I will do the best I can."

Poseidon nodded. "Beware the sky," he said quietly, already knowing that she would. His brother's temper had already cost Sally her parents' lives. "Zeus will strike you out of it the moment he learns you have borne my child. Never fly anywhere. If you must travel, go by boat or over land, and do not ever go to California."

"Why?" she whispered curiously as he pulled her into his embrace again.

"My brother Hades dwells there, underground. There is something about that place that draws monsters like bees are drawn to honey. You must never go there. Our child will be in grave danger if you do."

Sally nodded and leaned against him, taking comfort in his arms. She knew she would not be able to do so much longer.

"Stay close to the sea," he whispered, pressing his lips to the top of her head. "The closer you are, the easier I can try to protect you."

She nodded without saying anything, soaking up his warmth.

"Sally, will you promise me something else?" he murmured.

"Of course."

"Let our child know that I love them very much, and that if I could I would be here with you for every moment if I could. I . . . I don't want them to feel like I do not care. I do care. More than I can possibly explain in words." He smiled faintly and looked down at her. "Will you . . . will you bring them here? To Montauk?"

"Every year," she promised, smiling back.

"Thank you," he sighed, dropping his chin to the top of her head. "I will be watching."

"I know you will," Sally smiled, and marveled once more at how much she loved this man. "How much longer do you have?" she whispered.

"A few days, at most," he whispered back. "The longer I stay, the more danger I will put you in."

Putting on a brave face, she stepped away from him and smiled. "Well," she said with her usual cheer, "let's make the most of them."

Four days later, she awoke at the cabin on Montauk alone and immediately knew Poseidon was gone. She bit back her tears and rolled over to find a seashell on his pillow. She cupped it in her hands and curled into a ball, the tears streaming down her face.

She pressed her hand carefully to her stomach and whispered, "I'll protect you the best I can, little one."

"Oh, Percy," she whispered, stroking his tuft of black hair off his forehead. "Your daddy loves you, never forget that. And I'll try to keep you safe."

After a long six months in the apartment, Sally grew tired of her grumpy neighbors. It wasn't her fault that babies cry, for Pete's sake. So, she buckled Percy into his car seat, packed a bag, and headed to Montauk. She was hurting, and needed something to remind her of him. Just for now.

When they arrived, it was late afternoon. She booked the same cabin as before and got them all unpacked before kicking off her shoes and wiggling her toes in the sand. With her baby cradled in her arms, she stood at the edge of the surf, staring off across the ocean and thinking of him.

She waded out into the shallows and sat, the water level just above her belly button. Percy cooed and kicked his little feet in the waves, splashing his hands with a delighted giggle. She settled him carefully in her lap and just let him play in his natural element. A part of her wondered if Poseidon could see them. She hoped so.

Fish started to appear after a while, swimming around them, before growing brave and coming up to bump against Percy's tiny feet and legs. Percy giggled with delight and made cooing noises at them. A part of her wondered if they were speaking to him, and if so, what they were saying.

Sudden darkness made her glance upwards with a frown. Clouds were gathering, but that was far from rare on the ocean. Shaking off her suspicions, she smiled down at her little boy and watched with slight wariness as what appeared to be a baby shark swam up to them and nuzzled Percy's stomach, swimming in slow circles around them.

At least here, Sally had nothing to fear. Poseidon had told her no creature in his realm would harm their child. And so, she smiled when the shark nuzzled her hand as well before swimming a ways off through the growing numbers of fish.

/

Poseidon forced down his irritation as he left his room after an argument with his wife. She claimed he was distracted, ignoring him. In all honesty he was, he realized with a stab of guilt. For the past fifteen months, he had been greatly distracted looking over Sally.

She had remained on Montauk for much of her pregnancy, and he silently thanked her for that. He was able to watch as her body rounded with his child and had to constantly force himself to remain in the sea. All he wanted to do was return to her, be with her, help her through the birth. She left to return to New York, and he sensed when the child was born. There was a new link in his mind, an awareness of another tiny being that was a part of him. Two days later she brought the child to the seashore, and he saw his son for the first time from afar.

She had stood ankle-deep in the surf and smiled at the waves. "A son," she whispered. "I named him Perseus, Percy for short. I miss you."

And then, she had been gone.

He sensed she was near again, and dissolved into bubbles. They were at Montauk, he realized, as he watched them from afar while she sat in the calm waters with fish and young sharks swirling around them, Percy settled in her lap.

Son of the Sea God, son of the Sea God, son of the Sea God, the fish were whispering in awe in tandem with the young sharks.

Percy was bigger, he noted. His hair was longer, and he no longer had the look of a newborn. He was slightly chubby, and happily chattering away in babbles to the fish, who were ecstatic he was paying them any attention. He felt a smile curve his lips.

The angry rumble of thunder alerted him to the danger.

Poseidon abruptly solidified into his human-sized form and looked up at the raging storm clouds.

And then it hit him.

Hades. Maria di Angelo. The hotel. Zeus' bolt.

"No!" he cried in horror, rushing for them, calling the sea to his aid. "NO!"

He was too far away. He knew it before he started moving. The wave arrived at the same time a huge bolt of lightning arced down from the heavens and blasted the seashore, the fish and sharks fleeing in terror.

"No, no, no," he gasped, falling to his knees in the surf. Sally was still, her eyes open in surprise, sprawled on her back in the shallow water. With shaking hands, he reached down and pulled her up and into his arms. She was gone, as he had known she would be the moment he realized what was happening. "Oh, Sally," he breathed brokenly, tenderly stroking her cheek. "I wasn't fast enough. I am sorry."

He was only fast enough to shield his son. Percy was in the surf, crying in confusion and blinking, blinded by the bright flash and deafened by the extremely loud crack of lightning. The sea had helped to heal him, the lightning burns on his arms fading rapidly given his contact with the water.

Bowing his head, he kissed Sally on the forehead and watched as she disappeared in a shower of gold. Bitterness, pain, and anger swirled in his chest.

He would have words with his brother Hades momentarily, but for now, he needed to get Percy to safety.

As his emotions raged, the sea changed. It was no longer calm. It began to grow choppy as the waves grew larger, responding to his anger.

With gentle hands, he scooped up his son and waded into the water, murmuring soft words to him. Percy blinked owlishly, squinting as he tried to focus on his face.

"It's alright, little one," he murmured, kissing his brow, his cheeks, his chin. "You're safe with me."

Once they were fully submerged, his son started to yawn and just like that, fell asleep against his chest. Hoping beyond hope that Amphitrite would be forgiving, he imagined his palace and both he and his son vanished into the sea.

/

E/N: Recently re-read PJatO, and started to wonder what would happen if Poseidon had been betrayed by Zeus the same way that Hades had, and lost Sally in the same way Hades lost Maria.

This was what my brain fashioned as a result.

Reviews are appreciated! xD