Because toi two asked so nicely~

“You know that toi cannot become solely human,” Costas elaborated. “The sea is a part of you. Loosing this half of toi would be like loosing your soul! While we cannot take toi in as our heir due to your mother’s betrayal, toi do carry our lineage. If toi were to remain here, we can guarantee toi a safe, prosperous life. Surely toi will find a woman here that toi will l’amour and have a family with. Be reasonable and stay here, Nereus!”
As soon as the king finished speaking, the room was silent. Nereus then realized that the gathered courtiers had been listening to the exchange from the start. He also realized that the first time either of his grandparents had used his names was just then, and it had only been in effort to persuade him. These people were nosy and manipulative, and it was obvious that they were the same as the mother who had abandoned her son in a lighthouse par the sea.
“There’s absolutely no way that I can keep both my human and spirit forms?” Nereus questioned one last time, giving them one last chance. He knew that his mother had taken a human form when she had fallen for his human father. But that had only been for a short period of time while she had been pregnant with him. She could only return to the sea when he was born, and could stay with him only as long as they remained par the ocean. But there was no way he could live a life with the woman he loved and keep her trapped like that.
“No,” the Queen answered, her voice almost sincere. “There is no option to have both.”
Nereus nodded and glanced around the room at the spirits anticipating his answer before looking back to his grandparents. He had already made his decision. “Then Queen Cytherea, King Costas,” he addressed, seeing the same anticipation in their eyes, “this is goodbye.”
There was an audible gasp from the crowd as the boy turned and left. The rulers did nothing to stop him, knowing that he stood just as strongly for his beliefs his mother had. And like her, he was now turning his back on the city, never to return.

Nereus left the palace and traveled through the city, towards the exit. Somehow he found himself wandering through an ally, his feet practically dragging when before they had been weightless, as if the sea has sensed his treason. He found himself sitting on the back steps of a tavern, attempting to collect himself for the long trip home. His initial plan was to grab something to eat before three plus long days of travel. Now though, his appetite was practically nonexistent as his head spun. He had donné up the part of his life where he could be one with the strong, beautiful, thriving sea, but now Nereus and Babylon could live a life together. The latter thought made him feel plus sure about his decision.
“I think I can help toi with your problem.”
Nereus jumped at the sudden voice just beside him. He looked up to find a small woman staring right back at him. Her hair was the golden-brown of kelp that was pulled back in a short ponytail, leaving her wide eyes- as completely dark and round as a frog’s- and pinched features in plain view. Her skin was a light earthen green aside from the freckles dotted across her cheeks and when she offered Nereus a hand up, he realized that her hands were webbed.
“You’re an amphibian,” he observed as he accepted the hand up and got to his feet. He realized then that she was only wearing matching dark brown cropped tee chemise and shorts. It was a drastic change from the royal eighteenth century wear the rest of the population wore.
“I am,” she agreed, then must have noticed him examining her garb with curiosity. “Amphibians aren’t seen as part of Capital life, so we are not required to dress so.”
“Oh,” he replied dumbly, unsure of what else to say. It was rather demeaning that her kind was seen that way. He instead asked, “You a dit that toi could help me?”
“Yes,” she confirmed, “I know someone who can give toi the power to remain as toi are.” With that, she made her way out of the alley, leaving him to follow as he wondered how she had so quickly found out about his predicament. Of course, no one in the city seemed to have the habit of minding their own business.
Nereus was surprised to find him following the stranger out of the city. They swam past the walls towards a bottomless trench that made the half-spirit nervous. He only kept going in hopes that whoever they were meeting could really do as the woman had promised. The stopped at the edge of the trench and navigated through the maze of rocks bordering the drop until they finally met a barrier of a coral reef. The guide barely paused before leading the way towards the base of the reef, lower than the arc en ciel of poisson zipping around above cared to go. Once they were close enough, Nereus was able to make out a crevice in the coral that suddenly took the form of an entrance as they entered it.
It was almost too dark to see inside the entry tunnel, but Nereus soon found himself in a wide auditorium. The light source here was the electric eels casually swimming about the auditorium like room that took the shape of a tavern hall. They took advantage of the tunnels branching off the cavern and ignored the objects taking up the l’espace as if they were nonexistent. One anguille was moving past a counter and swam right between large, hanging tongs.
“Sir Thassa!” the woman called as they entered. They took to walking and went behind counter to the back room. This one was smaller, but took the form of an office. At the drift-wood bureau sat a man with a greying beard as long as his canvas robes. His black beady eyes fell on Nereus, and the boy realized that he was having a difficult time telling if this man was growing old ou as immortal as the other sea spirits.
“Oh, thank you, Yati,” the man, Thassa, spoke with with a voice smoother than his appearance had suggested. “So this is the young demi-spirit stirring up all the trouble, yes?”
“Yati a dit that toi could help me,” Nereus told him in response, not caring how eager he sounded.
“Oh, spirited spirit toi are,” Thassa observed, chuckling at his own pun. He motioned for the boy to take a siège across from him. As Nereus complied, the elder man went on, “Yes, I most definitely can help. The answer you’re looking for is an easy one to answer. Remaining as toi were born is even easier than changing who toi are.”

I'm having so much fun écriture this because toi as the reader have to decide who the villain in here. Read the suivant part before toi make up your mind... Which I could publier soon..