I recommend the novel One Piece: Prison of the Dead. The protagonist Qin Ge accidentally transmigrated to One Piece's world, and there was a prison in his body. This prison could imprison the souls of the dead in various worlds. At the same time, it could also allow people to obtain the abilities of the souls of the dead when they were alive.
It could be a corrupt ninja from another village who wants to get rid of Naruto as he sees him as a threat to his own plans. This ninja could have framed Naruto to send him to prison.
Maybe Danzo could be the main antagonist. He has always been a bit of a shady character in the Naruto series. He could see Naruto as a threat and use his influence to frame him and send him to prison to further his own political or power - hungry goals.
It could be a mysterious hero or a villain. The possibilities are endless!
There could be an ancient and evil force that has infiltrated the demigod world. This force uses Percy as a scapegoat and arranges for him to be sent to prison. It wants to cause chaos and destruction within the demigod community. It manipulates the situation from the shadows, and Percy has to figure out its identity and motives while in prison in order to stop it.
There were two novels that he could recommend, One Piece: Prison of the Dead and Blue Prison: Top of the World. The story of One Piece's Prison of the Dead revolved around the main character, Qin Ge, transmigrating to One Piece's world and discovering that there was a prison inside his body. This prison could imprison the souls of the dead in various worlds. At the same time, it could also allow people to obtain the abilities of the souls of the dead when they were alive. On the other hand," Blue Jail: Top of the World " was a juvenile comical drama. The story revolved around the main character, Yotaka Micang, and a series of supporting characters. These two novels are set in prison and might suit your needs.
The main character of Mummy 1 started out in prison. In the novel The Mummy, the main character, Matthew Holmes, was initially portrayed as an anti-hero who spent a long time in prison and was sentenced to death for murder. In the novel, Matthew's prison guard was a female police officer named Emily Pliny. She was very cold to him and used him for her own personal gain. As time passed, Matthew gradually realized that he had been framed and began to search for the truth. In the end, he successfully proved his innocence and became a hero.
I recommend the novels "Guarding the Celestial Prison for a Hundred Years, I'm Invincible" and "Super Clone: I Become a God in the Black Prison". These two fantasy novels were about a prison guard without cultivation who used various opportunities to become powerful. In "Guarding the Sky Prison for a Hundred Years, I Am Invincible," the male protagonist, Su Chonglou, relied on the Holy Jail System to imprison prisoners in the chaotic world to become stronger. In "Super Duplication: I Become a God in Black Hell," the male protagonist, Han Sen, used his golden finger to copy the martial arts, heart techniques, and martial arts of the peerless masters. I hope you like this fairy's recommendation. Muah ~😗
I'm not a fan of online novels. I'm just a person who likes to read novels. I can't give an accurate answer about the novel with the main character called Leng Hanyu because I haven't learned enough about online novels.
In a 'naruto goes to prison' fanfiction, it could be that Naruto is tricked into taking the blame for someone else. Once in prison, he meets old foes who are also incarcerated. Instead of fighting them, he tries to understand their motives and in the process, he uncovers secrets about their pasts that were related to some greater threat to the ninja world. This knowledge then becomes crucial for his future actions outside the prison.
One possible plot could be that Naruto is framed for a crime he didn't commit. Maybe someone with a vendetta against him plants false evidence. In prison, he would have to deal with tough inmates and the strict prison regime while trying to prove his innocence.