Various animal features, high Ars Magus aptitude, high physical strength, long lives
Half-Beastkin are a hybrid species of beastkin and human.
For as long as they have existed, half-beastkin have been largely shunned by society - both by beastkin and humans alike. At some point, both Jubei and Tomonori openly accepted a large amount of them into their village before the beginning of the Dark War, knowing that none of the half-beastkin had anywhere to live. 
In more modern times, they still face stigma from society, and are put under the umbrella term 'beastkin' alongside other humanoid species with animal characteristics. Half-Beastkin are shown to be incredibly strong, have very long lifespans, and are potent in the Arts, inheriting positive traits from their parental species. Half-Beastkin inherit the subspecies traits of their parent beastkin, demonstrated with Kokonoe inheriting her father's cat ears and tails. Unlike beastkin, half-beastkin have a much greater command and use of Ars Magus. 
Of all the species catagorized as 'beastkin', half-beastkin are perhaps the rarest as beastkin themselves are already exceptionally rare.
- Numerous half-beastkin under Tomonori's command before the Dark War
BlazBlue: Central Fiction Library Entry
Refers to humanoid beasts such as Taokaka and Jubei. They have high physical abilities and long lives, among other traits. Kokonoe is a 'half-Beastkin.'