Humans are the most predominant race in the Human Realm who were naturally born in this state. The normally posses no superhuman abilities unless they are hybrided or well equipted in both class and weaponry. Humans have the choice due to the opposite realms to work to salvation for the afterlife or abandon morality in order to become a Demon of great power.
Humans are the natural born species of the Human World. They are average beings with no supernatural abilities but a positive kharma that ensures them an afterlife aslong as they believe in their own salvation. This kharma can be after death to journey to the afterlife and become an angel that guides the rest of the human race from above.
Or it can be turned negative in order to choose the path of the demon which gives Humans unimaginable powers but leaves them with little chance of journeying to the afterlife unless they decieve the demonic realm and use their powers for the right. Although that is nearly immposible since the demonic tendencies normally take over their mind, but there are few who are able overcome this and return to their human state of mind.
Humans are normally unable to combat even the weakest of demons, but some train themselves in classes in order to strengthen themselves. These classes include Swordsmans, Reapers, Gunners, Archers etc... that use weaponry in order to combat the supernatural abilities of a demon. These weapons can be improved throughout time to even match that of a Devil Arm and weapons such as amulets can cast magic similar to that of a Demons.