Ghost Night book 1. First in this series, with a definite and sharp change of plot lines -- but still, serious spoilers ahead for the Ghosts and Ghost Exile.
It opens the night after Kylon and Caina marry. Where they are attacked by a magical vortex that sweeps them off. Both of them find themselves alone -- and naked -- in a mysterious structure, where Caina finds a forlorn girl, Sophia, and undead monsters, and Kylon a battle magus, Seb, fighting the Adamant Guard, before they find each other. Also, Caina breaks through some wards to escape, and finds a ring.
It goes on, with Sophia's claim that she would suffer for stealing a sunstone, Seb's startling resemblance to Ciana, a Bronze Witch who can appear and disappear, bear traps, men with wolf spirits, and more.