I stumbled across this essay on the legality of fan fiction. It appears on the website of the Literary Review of Canada.
Friction Over Fan Fiction: Is this Burgeoning Art Form Legal? by by Grace Westcott.
It is an interesting read. At least, I thought so.
And, with the article fresh in mind, I return to copyright infringing working on a story, in hopes that my muse will be intrigued enough to come back.