It sounds like there are some supernatural elements to it so I might go with paranormal romance more than mystery...but that's just my opinion..sounds interesting :)
I found this on wikipedia which might help:
Paranormal romance blends the real with the fantastic or science fictional. The fantastic elements may be woven into an alternate version of our own world in an urban fantasy involving vampires, demons, and/or werewolves, or they may be more "normal" manifestations of the paranormal—humans with psychic abilities, witches, or ghosts. Time-travel, futuristic, and extraterrestrial romances also fall beneath the paranormal umbrella.
These novels often blend elements of other subgenres—including suspense, mystery, or chick lit--with their fantastic themes. A few paranormals are set solely in the past and are structured much like any historical romance novel. Others are set in the future, sometimes on different worlds. Still others have a time-travel element with either the hero or the heroine traveling into the past or the future. Between 2002 and 2004, the number of paranormal romances published in the United States doubled to 170 per year. A popular title in the genre can sell over 500,000 copies.
Many paranormal romances rely on the blend of contemporary American life with the existence of supernatural or magically empowered beings, human or otherwise; sometimes the larger culture is aware of the magical in its midst, sometimes it isn't. Some paranormal romances focus less on the specifics of their alternative worlds than do traditional science fiction or fantasy novels, keeping the attention strongly on the underlying romance. Others develop the alternate reality meticulously, combining well-planned magical systems and inhuman cultures with contemporary reality.
posted 3 years ago. ( permalink )