are naiads mentioned in modern fantasy

It's possible. There could be other demigods or mythical creatures. Maybe a centaur who gives Percy some advice regarding the naiads. Or a sea monster that they have to face together.

In some fanfictions, Grover, Percy's satyr friend, might also be an important character. He could accompany Percy when he encounters the Naiads. And there could be a particular Naiad that stands out more than the others, perhaps one with a unique personality or special powers. For example, a Naiad who has the ability to control not just water but also the plants around her water source.

" Fantasy: I Become the Imperial Ancestor " is a fantasy novel written by author 12345. The general plot of this novel is: What? I actually became the Imperial Family's Patriarch? I, Rong Kingdom, am going to be destroyed? Ding!" Congratulations to the host for activating the Rise of the Strongest Empire System!" " Unlocking the main mission. Unify the world and become the strongest empire in the world!" " Activate the side quest. Repulse the enemy country and recover the lost territory!" How dare you invade my Rong Kingdom? You're courting death! With the system in hand, the world was mine… ---------------------------- The book " The Unparalleled of the Three Kingdoms " was written by the author, Wu Sansheng. It was a virtual online game novel. The general plot of this novel was: The entire map of Empire was a world map that had been expanded by a thousand times. The borders of each country were determined by the borders in reality. Of course, players in Empire could start a country war and invade other countries. Two people asked me to create a group. I'll create one now. I think someone will come in... ---------------------------- Divine Emperor was a fantasy novel written by the author, Nian Hua himself. The general plot of this novel was: Reborn in another world, with the help of the system, become the strongest emperor... ---------------------------- Lao Zi is the Strongest Emperor was a historical novel written by the author, Pingfan. The general plot of the novel was: Traversing the world of history, awakening the memories of the supreme divine emperor of the myriad worlds in his previous life. Here, the empire had immortals guarding it. Here, you will see a grand world, a magnificent fantasy historical world. Here, the main character would use his Supreme Saint Emperor body to suppress the world and create a sacred dynasty. ---------------------------- " The Eternal Emperor " was a fantasy novel written by the author, Four Seas 1 Sunny Day. The general plot of this novel was: Fantasy, war, leveling up, and invincible talent. Book friends who like these can take a look... ---------------------------- The book " The Supreme Emperor " was a fantasy novel written by the author, Please Call Me Huang Daxian. The general plot of this novel was: The story took place in the Heavenspan Continent, a world where martial arts were respected. There were two races, humans and demons. The main character's empire was the Ancient Wind Empire, and there was another Ancient Cang Empire that was evenly matched with the Ancient Wind Empire. Among them, the Ancient Wind Empire had three major sects, the Pride Sect, the Heaven Destruction Sect, and the Fallen Moon Sect. The Ancient Cang Empire had two major sects, the Emperor Heaven Sect and the Qi Hui Sect. Let's see how this poor kid can become a Supreme Martial Artist… ---------------------------- 'The Strongest Emperor of the Myriad Worlds' was a fantasy novel written by the author, Monarch Ziyun. The general plot of the novel was: In the myriad worlds, who ruled over the ups and downs? There were billions of worlds, thousands of races, saints dominating the world, the Supreme Fate Dynasty sweeping across the eight wastelands, the Merit Holy Land spanning thousands of worlds, the Great Era coming, the evildoers rampaging, the prodigies endless, Ying Qi bringing the strongest emperor system, summoning civil officials and generals, forging the strongest Fate Dynasty, becoming the strongest emperor... ---------------------------- The King's World was a novel written by the author, Invincible Cyan Shirt. The general plot of the novel was: He once established the State of Qin in Huoying, and established the Ninjutsu civilization side by side with the five great countries. He had once conquered the great sea route with pirates, challenged the four emperors, and established the Demon Fruit Civilization. He once sat on the immortal sword and held Mount Shu. The south of the South Mountain was the hilt of the sword, and the north of the North Sea was the body of the sword. He used the sword to kill all lives and established the sword immortal civilization. He had once crossed the boundary between life and death from the Grim Reaper, transformed into the King of Hell, and forged an eternal divine kingdom! He had once traveled to the West and crossed the Five Elements Mountain, facing the West side by side with the Great Sage. Billions of soldiers had become the overlord of a region! In the technological world, he used a universe ship to travel through the starry skies and see the myriad worlds of stardust. He had once sat down coldly with the various kings in Heaven Covering, God Tomb, and Coiling Dragon to divide the world's resources. The Myriad Realms, the fusion of civilizations, and the creation of a supreme divine kingdom. This country spans thousands of worlds. Billions of living beings were the King's weapons, billions of realms were the King's garden, and billions of civilizations were the King's foundation! This was the King's World! P.S." One Piece's Strongest Possession " 1.93 million words has been completed. Book Group: 238274573 . ---------------------------- I Am the Emperor in the Heavens was a fantasy novel written by the author, Xing Batian. The general plot of this novel was: In the Three Kingdoms of Immortal and Martial, generals refined their spirits, strategists refined their spirits, and they fought against the heavens and earth with unparalleled divine might. Becoming a prince, controlling the dragon spirit, piercing the heavens as an emperor, collecting the dragon qi of the alien races, turning the tide and helping the building to collapse! . ---------------------------- The book," The Eternal Emperor ", was a fantasy novel written by the author, Mountain Ghost of Fallen Star. The general plot of this novel was: Ling Tian held the Emperor Rubik's Cube! He would conquer the empire, shake the Celestial Realm, destroy the Divine Kingdom, destroy the Holy Land, and unify the world! "My Emperor Ling is the only one in history!"

I'm not sure specifically as I haven't read this particular fanfiction. But it might involve Percy having some sort of adventure or encounter with the naiads. Maybe they go on a quest together or there's some mystery in the underwater world that they have to solve.

One idea could be Percy helping a Naiad protect her water source from pollution. He uses his demigod powers to fight off the forces causing the pollution.