Nightborns are a race in Astralis.
While there are no clues as of yet as to where or how the Nightborns originated, local folklore say they are mostly human beings blended with some sort of ghastly properties on their life essence. All nightborns share common feats such as the extended attunement to their current environment, and a few more abilities only reserved for nightborns.
Given these special traits that would make them good thieves and assassins, a lot of them don't really use their innate capabilities at the expense of others. Because of their nightly powers, nightborns usually feel elusive about humans because they feel they are biased against humans. Some humans, not more than a lot would make unclean judgments towards nightborns, seeing them as sneak-thieves and might-be-assassins.