Otherworld challenger - Jane Godman

KING OF THE OTHERWORLD

The race is on the find the true heir to the faerie crown before the evil king Moncoya returns from exile. Mercenary necromancer Jethro de Loix will find the challenger to Moncoya's crown.for a price. One million mortal dollars. Outraged at Jethro's audacity, Princess Vashti, Moncoya's daughter, arranges to accompany him on his mission.

Jethro doesn't want company, especially not from Moncoya's belligerent, pampered daughter. But as their journey pits them against evil forces, their animosity soon gives way to an overwhelming physical attraction between them. When the trail ends on the legendary Isle of Avalon, can the pair face down the evil sorceress Morgan le Fay to claim a future they'd long denied themselves?