Diablos is Devil, also known as Lucifer or Satan that mentioned in the Bible and the New Testament. Diablos defined as the arch rival of God and the temptation for human. He is the most powerful of all the fallen angels and was expelled from heaven because of his arrogance.
His appearance or representation looks like a red creature with a long tail and thin just pointed and two horns on its head, usually associating the trident. Anyway, in the Christian culture, countless times that the Devil can be presented in front of indefinite forms of a human being, not only physically but in the form of temptations, dark desires ... Who will try to lead the victim "the wrong direction". His appearance more or less consistent with that shown in Final Fantasy VIII, where Diablos is a creature whose appearance reminds us of a fallen angel shape, with two horns and a tail, but in this case does not have any trident. In this game he called as "Dark Messenger" that bring fear to all of enemy that dare to face him.