Can I write a song about the plot of a visual novel? Do I need to get permission from the author in order to publish it?

Question

I tried to be as vague as possible in describing things, but sticking to the events in the storyline. The characters do the same things, but I do not mention their names. 
 
Essentially, I tried to make the story not be readily recognizable, but it's possible people do (I don't know how effective I was in avoiding that). 
 
Another thing is that the visual novel is free-to-play (though there is a paid version with additional features), so I don't know how that would affect things.

James L. Arrasmith · Answer

Your situation touches on an interesting area of copyright law regarding derivative works. While you can't copyright ideas or general plot elements, the specific expression of those ideas (including character development, dialogue patterns, and unique plot sequences) is protected. 
 
Creating a song based on another work's plot could potentially be considered fair use, particularly since you've made an effort to transform the material and aren't directly copying character names. The fact that the visual novel has a free version doesn't change its copyright protection, though it might suggest the creators are more open to derivative works. 
 
To be completely safe, you should either get permission from the copyright holder or make your song more transformative by significantly changing the plot elements and adding your own unique creative elements. If you're concerned about legal risks, you might want to consult with an intellectual property attorney licensed in North Carolina who can review your specific situation and the song's content in detail.

Q: Can I write a song about the plot of a visual novel? Do I need to get permission from the author in order to publish it?