Jann are mortals whos liniage has been mingled with the various races of genies, powerful magical beings from the elemental plains.
Jann often have strong characteristics reminesent of the element of their genie relation. Decendants of an efreet may be hot tempered and resistant to fire damage. Marid related jann may be natural sailors and extraordinary swimmers. Etc.
Due to their highly magical nature, jann are often among the most powerful types of mixed bloods.