The male protagonist can split into two people, one with a devilish personality and the other with a cold personality. It is a novel from about five years ago.

I recommend "The Female Lead of Dressed Quickly, She's a Little Sick" to you. The female lead remembered that she had done all kinds of bad things in her previous life and died young, but in this life, she entered a system. The female lead had an antisocial personality and was a little sick. It was common for them to cause trouble and collapse the plane. The plane's male protagonist was still infatuated with her, and his body and mind were absolutely clean. At the same time, the other personality of the female protagonist also loved her deeply. The above is my personal recommendation. I sincerely hope you like it ~

I recommend "The Final Persona" to you. This is a sci-fi time-travel novel written by the author, Dream Eating Ice Luo. The story was about the male protagonist who died of a terrifying split personality, but he traveled to another world and turned split personality into his innate ability. The book also involved the efforts and struggles of the male protagonist in dealing with personality disorder. I hope you like my recommendation. Muah ~

The male protagonist, Yang Wenguang, transmigrated to the Origin Continent after his death due to split personality. His split personality actually became his innate ability. I hope you like my recommendation.

He could be portrayed through his appearance. For instance, one personality might have different - colored eyes or a distinct style of dressing. His behavior would also change. When in one personality, he could be very talkative and energetic, and when in the other, he could be silent and brooding.

I recommend the novel "I Am a Billion Doppelgangers" to you. This novel tells the story of a failed author who transmigrated to the world he wrote and became a character that should have died. However, he activated the golden finger, the Billion Doppelgangers System, so he could only tell others to die! The main character shuttled through various worlds to cultivate. Each clone had a different personality, which affected his cultivation and growth. I hope you like this fairy's recommendation. Muah ~😗

In "The Final Persona," the male protagonist transmigrated to the academy city on the Origin Continent due to an extremely terrifying split personality, and used split personality as his innate ability. I hope you like this fairy's recommendation. Muah ~😗

[Love Healing] is a modern romance novel written by the author Murong Wanqing. The general plot of this novel is as follows: The big show of torturing people to death had finally arrived! Because the female protagonist had cancer, she started to take an unusual path. Around her different stages of life, three extreme men appeared. When they found out that the woman they loved was actually a terminally ill patient and could die at any time, what kind of affection, persistence, cowardice, and deception would they have? Three men and a woman. What kind of dazzling, heart-wrenching, and inseparable love story had they experienced? Please look forward to the love abuse drama, Love Can Heal. ---------------------------- "The Sick and Delighted Prince Charming is Super Fierce and Cute" was a modern romance novel written by the author, Song Yushuang. The general plot of this novel was as follows: [Dark Female Lead x Hidden Sick Male Lead] "Don't talk to other women!" "Don't touch other women!" "You are mine, your heart is mine, and everything you have can only belong to me!" In her previous life, she loved Ye Chen to the point of sickness. When she was reborn ten years ago, before she was terminally ill, she decided to let him go and let herself go. However, she realized that he was the one who was really sick… "Niannian, don't leave me. If you want to leave, take my corpse with you." "Niannian, don't look at anyone else. Just look at me, okay?" [Little White's writing style, melodramatic plot. The male lead's early stage is a little lousy. Think about it before watching.] ---------------------------- "Struggling with Cancer" was a novel written by the author, Kaixia Juntian. The general plot of this novel was: This was a novel that recorded the story of the oncologist department in the hospital. It included the struggles of the medical staff, the struggles, sufferings, and persistence of cancer patients and their families, and countless medical science knowledge that told you how to take care of your body. I hope you like it! ---------------------------- You Were Once in My Heart was a short story by the author, Nian Zhihuan. The general plot of the novel was: Because of her love for him, she had removed one of her kidneys to save the person he loved. Because of her love for him, she had thrown her dignity on the ground and let him trample on it. Because of her love for him, she had endured everyone's abuse and insults and stayed by his side until a piece of broken cancer book came…Finally, it was enough of his young warmth. Then, on that stormy night, she dragged her damaged body and soul and completely disappeared from his sight. ---------------------------- "The Devil Boss's Innocent Lover" was a modern romance novel written by the author, Mian Fei. The general plot of this novel was: When they first met, she said,"You are the most beautiful person I have ever seen. I allow you to be my prince." A parting, a turmoil, changed everyone's fate. When the gears of fate turned her to him again, he held her chin tightly and said,"Say you like me." "You're crazy!" she roared. "You're wrong," he said with a slow smile. It's a mental illness. There's a fundamental difference between the two." ---------------------------- "My Boyfriend Has Separated Again" was a modern romance novel written by Mango Plum Jiang. The general plot of this novel was: "I'm rude, lecherous, and infatuated. I grind my teeth and snore when I sleep. My body is flat and it's not easy to give birth. So…"She handed over the divorce agreement with trepidation. "Whether they are compatible or not, it's up to me." The tall and handsome wife-doting demon approached him with an unpredictable expression. The seven personalities took turns."Let's try and see if you're really infertile." She couldn't afford to have seven husbands fighting for her favor! "Mr. Zhuang," she said regretfully,"split personality is a disease. It needs to be treated." [1v1, Sweet and Savage]. ---------------------------- "Top Female Hacker: Only You" was a modern romance novel written by the author, Luan Yi. The general plot of this novel was: His mother died in an accident, and his mother's twin sister secretly took over his mother's position at home, causing him to suffer from a disorder of contact with the opposite sex since he was young. She was the queen of hackers and his psychiatrist. She had many incredible survival skills, but she had never tasted the warmth of family. They had grasped each other's fate. The person he loved could only be her, and the person she loved could only be him. My heart has been wandering for too long, and no one can get close to it. The person I love in this life can only be you. ---------------------------- "Cannon Fodder Female Supporting Character: All Male Gods Come to My Home" was a modern romance novel written by the author, Mr. Troublemaker. The general plot of this novel was: The system had ordered her to go to Manny, a foreign land. Manny, this was a mysterious country where luxury cars were everywhere and money was flying everywhere. She became his wife, only to find out that her husband had multiple personalities. He was sometimes gentle and affectionate, sometimes cold and rough, and sometimes soft and timid… There were countless 'he's' living in his body. However, none of this was important. What was important was that when she was about to leave, he said to her,"If you don't want to stay, I'll go with you." ---------------------------- "Cure My Disordered Boyfriend" was a modern romance novel written by Qian Xia. The general plot of the novel was: It was a daily conversation between a cold psychiatrist and a popular celebrity. "Are you sick?" she asked. "Yes, I'm sick. Otherwise, why would I spend money to look for you?" She turned around and left. "You're sick!" she said. "I'm not sick!" he said. "If you're not sick, why are you looking for me?" she asked. He did not say a word. He hugged her and kissed her! He was cold, arrogant, and the playboy she hated the most. She was his psychiatrist, so she had to take care of him 24 hours a day. Damn, this is really like a sheep entering a wolf's den! "Do you dare to come?" A certain romantic celebrity said provocatively. She was a top-notch psychiatrist. If she said he was sick, then he was sick. If he was sick, then he had to be treated! The plot is fictional, please do not imitate it. ---------------------------- "The Duke's Wife Is Very Sick" was an ancient romance novel written by the author. The general plot of this novel was: How the male protagonist and the author met: What to do if the only heir of a wealthy family had a dual personality? Urgent, waiting online! Well said, well said (*^Omega ^*), after the baptism of hypnosis in his previous life, it was guaranteed that the disease would be cured! Really? It's not true! This…That…Maybe…I can try…Come on, come on, I'm sure it's a good bet. It's worth it, hehehe…I always feel a chill on my back. Is it a scam? Do you still have a choice? Flipping the table, cheers! As he continued, something was wrong with the plot. Why couldn't the male lead's halo overshadow the female lead's? Cough cough, I forgot to tell you something. This is a female channel…Nani? No, no, even if it's a female channel, Yours Truly will make him a male channel! Alright, if you can do it, then go ahead. Throw! You're such a willful author! Why didn't he have a bottom line? I'm so willful, what can you do to me?

I recommend the following romance novels with a male protagonist with a split personality to you: 1. "To Capture Gu Ai, See You Tonight, Mysterious Husband": The male protagonist had a complicated identity and had different personalities. In the story, the female protagonist discovered the secret hidden behind the male protagonist, and their relationship gradually warmed up. 2. "After Her Holiness": The male protagonist loves his wife, but is treated as a wretched uncle. The male protagonist also has a split personality, which tells the story of the deep love between the two. 3. "Black and White Angel: Who Do You Love?": The female protagonist has a serious split personality disorder. On one side is a simple high school student, and on the other side is a cold and dark woman. The male lead was a cold prince, but he could reach deep into the female lead's heart and communicate with her. I hope you like my recommendation. Muah ~

When writing a 'Harry Potter Split Personality Fanfiction', it's important to make the two personalities distinct. Maybe one Harry is brave and selfless like in the books, and the other is more cautious and self - preserving. Also, show how the split affects his relationships with Ron, Hermione, and other characters. For instance, Hermione might be the first to notice the change and try to help him figure out what's going on.