Update note c.2013: There have, of late, been a number of excellent entries in the so-called "paranormal" categories of romances, mysteries and so on, which have taken the concept of demons, along with angels, vampires, werewolves, and all kinds of other presumably mythical beings (such as Charlaine Harris's telepathic Sookie Stackhouse), complete with mixes and matches, and brought them into variants of the day-to-day modern world. Some have made it with various degrees of success into movies (Twilight, Harry Potter) and TV (how many vampire detectives can you name? Forever Knight premiered on CBS in 1992... over 20 years ago now!). The changes have been ringing for some time now, but while the story concept that brought Zrina forth was hardly new even at the time, Ted White suggested a particular variant to a gathering of fans in the 1960s, and, as I recall, the late Dave Van Arnam actually did write it up and it was put into print in Fantastic Stories, which Ted was editing at the time. I don't find a reference to it in Google, though.