Clan members have distinctive red fang markings on their cheeks, animalistic eyes, and enlarged canine teeth. It would seem that due to the bond between a Inuzuka clan member and their canine partner, their chakra is allowed to mix [Awesome] and is shared between them, adding a feral appearance to the human partners, and makes a bond between them that affords them the use of the clan's collaboration jutsu, such as the Dual Piercing Fang.