Ysabel

Ysabel is a 2007 fantasy novel by Canadian author Guy Gavriel Kay, his tenth work, and the first to be set primarily in the real world. It won the World Fantasy Award for Best Novel, as well as a few other honours.

Ned Marriner, a 15-year-old Canadian from Montreal, is visiting Provence, France, for a few months, because his father Edward, a world-famous photographer, is working on a new book there. Also along on the assignment are his father's two workmen, Greg and Steve, and his hyper-efficient personal assistant, Melanie. Ned finds all of this rather boring, though a few months off of school is nothing bad. Then, while visiting a cathedral, he runs across, first, an American exchange student named Kate Wenger with whom he immediately hits it off, and, second, a mysterious knife-wielding man raiding the cathedral's basement. The latter event is the beginning of a very unusual vacation indeed, which ends up involving possessive spirits, Celtic mythology, and Ned's mysterious aunt and uncle who he's never met before.

This book provides examples of:

 * Badass Boast: do this several times, but.
 * Badass Normal: Several characters.
 * Canon Welding: Though not marketed as such, partway through it is revealed that.
 * Demonic Possession: Not technically a demon, but that wouldn't matter tremendously to the people involved.
 * Full Name Basis: Particulary Kate Wenger and Edward Marriner.
 * Gambit Roulette
 * Hooked Up Afterwards: Confirms that.
 * Hypercompetent Sidekick: Melanie.
 * Locked Into Strangeness:
 * Love Tropes
 * Love Hurts
 * Love Makes You Evil: A lot of people have died over the centuries because of this lovers' quarrel.
 * Love Ruins the Realm: As Cadell sees it.
 * Love Transcends Spacetime
 * Love Triangle
 * Mrs. Robinson:
 * Murder the Hypotenuse: Over and over and over again...
 * Reincarnation Romance
 * Those Two Guys: Steve and Greg.
 * Undead Tax Exemption: Averted; tries this, but her stash of money has been paved over in the intervening decades, and it was in francs anyway, so the Euro would have made it rather difficult to use.
 * Urban Fantasy
 * White and Grey Morality