Dream magic - Joshua Khan

In a world ruled by six ancient Houses of Magic, a girl and a boy
begin an epic and dangerous
journey of discovery . . .
Lilith Shadow, princess of darkness, is struggling with her growing
powers. Castle Gloom is filling with ghosts, zombies roam the
country and people throughout Gehenna are disappearing. Then Lily
is attacked in her own castle by a mysterious sorcerer known as
Dreamweaver and his army of jewel-spiders whose bites send victims
to sleep. Thorn, and his giant bat Hades, must save Lily from the
realm of sleep and help her overcome the evil Dreamweaver in order
for her to reclaim her kingdom.