She was like a mermaid with an unknown secret. Are there any similar novels to recommend?

I'm sorry, but the information provided by the given paragraph does not include the two novels, The Mermaid Effect and The Desaro Mermaid. I can recommend you other mermaid romance novels, such as "Young Master Li, Your Wife's Tail Loses","His Mermaid Lady Loves Candies","The Mermaid Baby in the Galaxy", and so on. I hope you like my recommendation. Muah ~

😋I recommend the following novels to you, I hope you will like them: 1. [Shark-Hunting] 2. Tears of Shark 3. The Way of Qi 4. "Mythical Love Story: The Tale of the Mermaid" 5. "Mermaid Beauty" 6. [Moon on the Vast Ocean] 7. The Phoenix Empress 8. Beautiful Mermaid 9. The Legend of the Mermaid in the Goatskin Book 10. My Mr. Merman All of the novels mentioned above contained the plot elements of the female protagonist being a mermaid. I hope you like this fairy's recommendation. Muah ~😗

I strongly recommend "The Indifferent Genius and Fiery Woman" to you. The female lead of this romantic youth novel, Shangguan Xiao, fits this description perfectly! Although she had a hot temper, she also had a delicate face and a smart mind. There were very few people who could resist her venomous tongue. Although he was cold at first, he was actually filled with a desire for love and friendship deep down in his heart. He liked to read romance novels. At the same time, in the novel, she also had the image of a good girl recognized by the class. I hope you like this novel. Muah ~

I have no idea who the unknown comic is. Maybe they haven't gained much publicity or recognition yet.

There is also 'The Mermaid's Sister' by Carrie Anne Noble. It tells a story about a girl and her mermaid sister. It's a story full of family bonds, mystery, and a touch of magic that doesn't involve adult content.

"Three Treasures in One Birth: Mermaid Mommy's Fierce Milk" [The plot is as follows: The female protagonist is a mermaid. Later, she met a mysterious big shot. Three years later, she became a top-notch celebrity and faced many suitors such as the Best Actor and the Medical Doctor. Finally, she got together with a big shot who had yet to be enlightened.] Ending words: I hope you like this fairy's recommendation, muah~

Another one could be 'Sword Art Online'. Although it has a different main theme of a virtual reality world, it shares the aspect of character growth and discovery like 'Secret Class' light novels. The characters face challenges and grow as they progress through the story.

"You're My Starlight Skyful". This book was a story about a young man who kept improving himself. The female protagonist was a top student who had a crush on the male protagonist. The male protagonist was the female protagonist's neighbor, who was also a top student. They admired each other but could not be together because the male lead had a girlfriend. I hope you like this fairy's recommendation. Muah ~😗

Tushan Reddie had many secrets in Little Fox Demon Matchmaker. First of all, she liked red very much because it gave people a warm feeling and could move her heart. Secondly, she was a very delicate girl. Red could show her personality and charm.  In addition, she liked to patrol the city walls. This could be her love for Mud Mountain, or perhaps she was searching for something. At the same time, she also had an incomparably powerful demonic power that made all the demons tremble in fear. Her demonic power was born from suffering. Once, when she was still in her loli form, she and Rong Rong were captured by a Taoist priest and were about to be sold to the "Heavenly Immortal Courtyard". Along the way, they were tortured. At night, a scar-faced little Taoist boy quietly came to the place where they were imprisoned. Reddie mistakenly thought that the Taoist boy wanted to harm her, so she accidentally killed him. These were some of Mud Mountain Reddie's secrets. While waiting for the TV series, you can also click on the link below to read the original work of " Little Fox Demon Matchmaker " to understand the plot in advance!

Red Mud Mountain was one of the main characters in the Chinese manga " Little Fox Demon Matchmaker " and its derivative works. She was the leader of the Demon Alliance and the King of Mud Mountain. She had a gentle and kind side, but she also had a domineering and cold side. Her secrets were: 1. Her real name was Tushan Honghong, and Tushan Susu was the little girl she had become after losing her demonic power and memories. 2. She once liked Dongfang Yueyue, but in order to protect Mud Mountain and the peace of mankind, she chose to give up her feelings. 3. Her unique skill was the insulated claw, which could ignore all magic power and magic treasure defenses. It was one of the most powerful attacks of the Mud Mountain fox monster. 4. Her magic treasure was the Tear of the Void, which could open a passage between humans and the demon world. It could also be used to store items and memories. 5. In her previous life, she was Mud Mountain's Honghong, the leader of the Mud Mountain fox monsters. She had a love story with Dongfang Yueyue that was engraved in her heart. 6. Her reincarnated partner was the beginning of the month of Pingqiu, and they completed their reincarnations under the Tree of Bitter Passion in Mud Mountain. 7. She had been controlled by Lady Black Fox in the Southern Kingdom chapter and lost her rationality and memories, causing great harm to Tushan Susu and Bai Yueyu. 8. In the 109th chapter of the manga, she sacrificed herself to protect Mud Mountain and humans, dying together with Lady Black Fox. While waiting for the TV series, you can also click on the link below to read the original work of " Little Fox Demon Matchmaker " to understand the plot in advance!