I have no objections to fans of my books writing their own fan-fiction around my works with the following caveats:
1. Please contact me in the first instance. I’m unlikely to turn down your request, but it’s just polite to ask. I’ll be happy to give you some advice. I will need to read the story in its entirety in order to give my blessing. I reserve the right to advise you on tweaks and suggestions if I feel you’re not interpreting a character correctly.
2. You must only distribute your work under the Creative Commons “Attribution-NonCommercial-ShareAlike” license. This must be stated at the front of your book/document when you publish it and the conditions fulfilled. You must not distribute your fan-fiction for commercial gain.
3. You must ensure that my characters remain my copyright. This must be acknowledged. I suggest the following wording.
<Character Name/s> is/are assets from the book <Book name> by Drew Wagar and used here with kind permission.
4. If you want to base your story on or use characters from my Elite Dangerous novels you must adhere to Frontier Development’s guidance on the subject. They’ve generously provided a means for you to do this. I refer you to their information, please read and observe it. I suggest the following text is placed in your document.
“<Name of Project> was created using assets <and imagery> from Elite Dangerous, with the permission of Frontier Developments plc, for non-commercial purposes. It is not endorsed by nor reflects the views or opinions of Frontier Developments and no employee of Frontier Developments was involved in the making of it.”
5. If you want to base your story on or use characters from my Midnight Chronicles novels you must seek approval from Chris Wild via the Lords of Midnight Website. I am not the copyright holder for Mike Singleton’s original works, so please ensure you gain Chris’ approval before writing anything!
6. The content must be appropriate. It goes without saying that I won’t endorse a story which contains any inappropriate content. I don’t think I need to elaborate on this nowadays, but consider it said anyway. 😉