Weredogs are therianthropic humans that appear mostly in fictional materials from around the world. The weredog is thought to be the latest take on the wide range of were-creatures seen though recent history. They are closely related to the original werewolves in there ability to take the form of a canine, however it is generally that of a domestic dog.
Unlike most other shape-shifters such as the werecat, the weredog is not seen very often in folklore and has less of a variation in appearance, although weredogs are considered to be the least violent of were-animals.
"Origin: Tokyo. Beastmen created by an alteration operation. Other demons that take a dog's form include Anubis and Orthrus. Perhaps by association, many Weredogs are given the duties of guards as well."
—Shin Megami Tensei A-Mode DDS Dictionary
The Dictionary reference to an alteration operation suggests that Weredogs are the attempts at super-soldiers that Orias is creating from his captives in the hospital.