Desertion

High Mage Kelderin is determined to learn the secrets of the unnatural blood-drinking strangers camping in Garantha's remote woodland, but his duties to the crown make it increasingly difficult to indulge his curiosity. War threatens, and the King requires Kelderin's services for a particular specialty: demon summoning. But demons are not beasts to be toyed with lightly.

This 15,961 word novelette is set in the Worldwalkers Universe.