It's an ethereal entity that manifests itself when a weilder of the Noryokugan synchronizes with their Cosmic Energy or a Shingengan weilder sychronizes with their spirit or spiritual energy. It appearance is that of a bird with organic/mechanized armor. In all cause it will move according to the users movement, some users are able to command it to move on its own, and it can even adhere to the users body like armor or upscale or downscale its size, depending on the will of the user. After years of mastery over it, it will develop weapons and/or defenses with abilities similar to those of their respective users dojutsu, though this is not always the case. The user is also able to channel their attacks through the entity to upscale them to a much greater level.