Which Mermaid BL Stories Feature Unique Underwater Worldbuilding?

In the shadows where sin and desire collide, Dark Desires delivers raw, unfiltered BL/MM erotica that pushes every forbidden boundary. Power-hungry mafia heirs, bloodthirsty vampires, ruthless professors, and fallen priests—all consumed by obsessions they were never meant to touch.

Adrian died with fury in his heart, hating the tragic ending of his favorite novel. The villain deserved better. But the story was never written for happy endings. Betrayed by everyone he trusted, feared by the entire world, and ultimately destroyed by the plot itself—Cassian Nyx, the infamous Demon Lord, was never meant to be saved. Until Adrian woke up inside the story. He didn't reincarnate as a harmless bystander. He woke up as Prince Elian Ashford—the tyrannical prince destined to destroy Cassian. Worse, a cold, ruthless World System instantly locks onto his soul, forcing him to keep the original tragedy on its "correct" path. [MISSION: MAINTAIN STORY STABILITY] Failure Penalty: Immediate Death. Trapped between a lethal penalty and his own morals, Adrian chooses a dangerous path: pretend to follow the plot while secretly rewriting the villain's destiny. But there’s only one problem. The more Adrian tries to save the villain, the more the dangerous, obsessive Demon Lord begins to love him. Cassian Nyx is a monster feared by the entire kingdom. He trusts no one. Until Adrian. For the first time in centuries, the scarred Demon Lord begins to hope for a future where someone finally stays. Now, the original hero has arrived, and the System is forcing the final execution. Every choice Adrian makes pushes the world further into chaotic plot deviation. Adrian must make his final choice. Will he obey the System to save his own life? Or will he destroy the entire story itself just to save his villain? Genre: BL Fantasy Romance / Transmigration Tropes: Obsessive Demon Lord ML × Reincarnated Prince MC, Saving the Obsessive Demon Lord / Destroying the Plot for You, System Missions, Enemies to Lovers, Slow Burn, Angst with Comfort, Soul Bond.

This is a story between a bloodthirsty merman and a kind and naive researcher. Linda, a researcher at a Japanese maritime university, found herself raped by a lewd merman in a dream. This tempted her to conduct research on this mythical creature. Together with her professor Gary, they set off to sea in search of merfolk. They successfully caught a merman, but Linda was marked as its mate…Was it a human that had caught a merman, or was it a merman who had found its prey?

Hunter Brantley is a gorgeous bad boy who takes a drive to the beach. That's where Hunter finds her. A beautiful, mysterious girl with aqua blue hair. She's half naked, lying on the beach sand and at the mercy of a stranger. Only she's not any normal girl. She is a mermaid. And Hunter is not such a bad guy, so he takes her home. Blue is a shapeshifting Mermaid who shape-shifts into a human when on land and turns into a mermaid underwater. What happens when she wakes up one day and finds herself on land in a completely strange place? Will Hunter be able to send Blue back to the Ocean or will she will be stuck with the bad boy forever ? A Romantic Comedy of a Bad boy teaching the Mermaid how to live like a human. What happens when the Bad Boy falls in love with the Mermaid? All Rights Reserved 2021 © KittyKash

Chloe is a scientist with a secret, she is a mermaid...without a mermaid, or so she thinks. She is a hybrid, half human and half mermaid whose father is disgusted and left her mother when he found out she was pregnant. With the help of her best friend Kari, who finds out she is Royalty in the Werewolf Kingdom, she finds herself fitting in with the Werewolves when the King of the Sea finds her. He is disgusted with her father for abandoning her and pulls her into their world along with her werewolf mate but she finds out that she is special and she is hunted for her mermaids scales

"Cry, Mermaid!" a sharp lash sliced into my back, forcing a yelp from my lips. Screams and sobs surrounded me on all sides, but no one would save me. Strong hands caught me beneath my arms and yanked me from the water. It was time for Tail Cut. The operation lasted hours. I felt every last slice of their blades, every new tendon sewn into my muscles and nail hammered into my bones. I screamed. I begged. I begged for them to stop, for them to kill me, just ended the pain. --- I have a secret, I am a mermaid. I should live in the ocean, but my tail was cut and I only owned legs. After escaping to Asterion, I hid my identity. I thought I could finally live a peaceful life, until that day I met the famous bad boy, the future Alpha, Caspian. --- I felt a strange prickling on the back of my neck. I spun around just in time to see Caspian prowling towards me through the darkened wings, his blue eyes positively glowing. Sharp white teeth flashed as Caspian's lips unfurled into a lethal grin, "Hello Mate."