Which shelf?

Dear Annie,

A book just arrived at the store that's posing an unusual question: on what shelf does it belong?

Dark Lord: The Early Years by Jamie Thomson opens with the main character falling onto a suburban parking lot.  He calls for his lieutenant, who doesn't come;  he discovers his iron-taloned Gauntlets of Ineluctable Destruction have disappeared: he has "pink, pallid and pudgy" soft hands.  Police officers approach, reassuring him that an ambulance is on the way.  He tries to zap them -- puny humans! -- with various spells, all of them ineffective.

   "What's your name, kid?" asked Officer Johnson.
   The kid, for that's what he looked like, thought for a moment.  He couldn't remember his name.  No matter how hard he tried, he just couldn't.  But he could remember what he was, and his primary  title.
   "Daa . . . (cough, cough).  I am the Dark Lord," he said.  To his horror, he realized his voice really did sound like some kind of do-gooding Elf woman or a human boy-child!
   "Dirk?  Did you say Dirk?"
   "No! No!  Dark!  Dark Lord."  But his voice came out wrong, weak and raspy and even more boyish than before.
   "Dirk, eh? Dirk Lloyd? Where are your mom and dad, Dirk?  Have you been hit by a car?  Are you lost, son?"
   "Mom and dad?" he sputtered, outraged.  "I don't have parents, you curs -- I am the Incarnation of Evil! The World Burner! The Dark One, to name but a few of my titles!  I'm not someone's little boy, you fools!"
   "These computer games.  It's an obsession at their age," said Officer Johnson.

Dirk eventually ends up living in a foster home, and in counseling.  He reluctantly makes a few friends in school -- and the story goes on to an excellent ending (stay tuned for book 2).  Throughout the book, one tries to figure out if this kid is the victim of a concussion and too many video games, or if what we're reading here is an interplanetary fantasy.  Needless to say, I'm not going to give it away here.

So here's my problem.  Our middle-grade fiction at the store is divided into two sections: one is fantasy and science fiction; the other is more realistic fiction.  If the ending shows that Dirk is a regular kid with delusions, it should live on the realistic shelves.  If instead he really is the Dark Lord of another planet, well, it's fantasy.   And if I display it on either side of the aisle, I'm giving away the secret of the book.  Right now it's on a new-arrivals display, so I'm sidestepping the question.  But sooner or later, I'll need a plan.

This theme -- mixing up florid constructs of fantasy worlds with everyday life -- is less ambiguously (but more artfully) presented in
What Came from the Stars by Gary Schmidt, author of Okay for Now.  I'm quite fond of his books, and this one is definitely a departure.  It opens in italics, in a world sounding vaguely Middle Earth-ish:

   So the Valorim came to know that their last days were upon them.  The Reced was doomed, and the Ethelim they had loved well and guarded long would fall under the sharp trunco of the faceless O'Mondim and the traitors who led them.  The Valorim looked down from the  high walls of the Reced and knew they would find no mercy in the dark fury of the O'Mondim massed below -- none for all they had loved.

So they forge a magic chain, containing all the knowledge of the Valorim, and toss it into their sky, and on up into space.  It lands in the lunchbox of Tommy Pepper of Plymouth, Massachusetts, planet Earth, on his 12th birthday.  It's cool looking, he puts it on, and he starts knowing things, like that a hanorah is a kind of horn: "You play it after a victory in battle, and also after Second Sunrise on the first day of the new year."  He's met with the same kind of skepticism that greeted Dirk Lloyd.
 
What Came from the Stars packs more emotional punch, though.  Tommy and his family are still reeling from the  blow of his mother's death.  Yes, it's another dead mother book, but the feelings are central to the plot; it isn't just a convenient way to remove an authority figure.  Evil developers are trying to change the Plymouth seashore.  Realistic chapters alternate with the high fantasy of the world of the Valorim, where underground resistance to the conquerors is growing.  Bad guys are sent across the universe to find the chain, and the resistance sends a virtuous young warrior to stop him.  The reader really cares about both worlds, and when Tommy and Ealgar join forces, we long for things to be right both in Plymouth and in the home of the Valorim.

And I know which side of the aisle this one belongs on.

Love,

Deborah