Some might be based on real experiences, but a lot are likely exaggerated or fictional. There are so many shows and books about haunted case files. Producers and authors often add drama to make it more interesting, so it's hard to say all are real.
I recommend the following novels to you:
1. "Black and White Case Files"-a mystery detective novel. The protagonist was a retired special forces soldier who was facing a series of strange cases. The male and female leads formed a partnership and gradually developed their feelings during the investigation of the case. The story was compact and exciting, and the reasoning segment was very interesting.
2. "The Reborn Genius Fierce Girl"-a modern romance urban novel. The female protagonist was a genius in the cultivation world. When she ascended, she was plotted against by the male protagonist. After her rebirth, she thought that she was the Bandit Ancestor, the God of Police, and the Special Envoy. She was extremely powerful, and the story was compact and exciting. It was full of fantasy and supernatural elements.
3. "The Female Lead of the City's Rebirth, Tianxia"-a modern romance urban supernatural novel. The female lead transmigrated and was reborn, becoming a representative of a different world famous for her profound medical skills. The male lead and other friends were powerful with her, possessing super power, status, and money. The storyline abused the mistress and the bad guys. At the same time, there was a sweet and touching love line. It was magnificent and the road to counterattack was exciting.
I hope you like this fairy's recommendation. Muah ~😗
Since I haven't read the 'Case Files Adra Castle Light Novel', I can't tell you the main characters specifically. But usually in a light novel, the main characters are often the ones driving the plot forward. They could be heroes, heroines, or characters with special abilities or knowledge relevant to the events in the Adra Castle. You could try looking for reviews or summaries of the novel online to find out more about the main characters.
It's possible that there is a physical copy available. However, without more specific information about this particular 'Case Files Adra Castle Light Novel', it's difficult to say for sure. You could try reaching out to fans of the genre or relevant fan communities. They might be able to tell you if they've come across a physical copy. Another option is to search for it in local bookstores, especially those that specialize in light novels or Japanese literature.
One of the great things about this novel is the relationship between the characters. Richard and his assistant (or other relevant characters) have a complex and evolving relationship. Their conversations and how they support or conflict with each other in the face of various cases related to jewels are what make the story so fascinating. There are also moral and ethical dilemmas presented when it comes to the value and ownership of jewels, which add depth to the plot.
Another option is to look into public records or archives. Some libraries or government repositories might have accessible cold case files. But it might take some digging and following the proper procedures to access them.
Another important character is his student. She has her own unique abilities and often accompanies Lord El Melloi II in his adventures. Her growth as a magician and her relationship with her teacher are interesting aspects of the story.