Storyline
In this world, there is nothing but war; war of swords and steel, and wars of political might and deception. Great kings rise to the top, creating great empires, shining like a star in the darkness of the world, but like all things in the world, it soon collapses, the Great king soon forgotten and overshadowed by someone even greater; such is the fate of all worldly things. To be remembered is the greatest victory in this world full of deception, tyranny, and decadence. Demons feast well on the low emotions of men; only the most iron-willed can resist their temptations. Those great men who can spit in the eyes of the Demon lords of the underworld, those men are remembered; if not by their peers, by the Demons who know forever that his soul will forever remain free of their grasp long after his death; those souls who are less strong are simply a feast and quickly forgotten. Even greater are the mightiest magic users who can bind Demons to the greatest weapons of war, turning the Underworld against itself; however, countless arrogant sorcerers have tried the same, but always end up becoming a thrall of the blade instead of the blade become their thrall.
Kings and Queens rule this land, and more often than not Nobility rule lands were the Monarch cannot directly rule; there is a special place in a Demon's appetite for these arrogant rulers of men. The common folk lay oppressed by the boot heel of these rulers; the sheer pointless tyranny caused sometimes disgusts even the most otherwise evil of Demons; it is, on occasion, a Demon will lend itself to these common folk; a mutually beneficial action results; the Commoners rise against their masters, overthrow them, and take the handle of their own destiny, while the Demons get a succulent feast of blue-blooded souls. This is a cause of great strife; rebellions are common place, yet the rulers do not think that if they remove their tyranny then perhaps they will end; it is this that causes a vicious cycle. It is a great, or kind, leader who can end this rebellions peacefully, and turn to other Kingdoms to conquer; these men are not in history books, they write the history books. To unite this chaotic land, it would require the greatest leader of all time; countless have tried, none have succeeded. Dozens of kingdoms lay scattered about, all war-like, all blood-thirsty.
Now that the politics is understood, it is time to turn to the Underworld; the Demons who manipulate the mortal world. The area where they resides is called the Underworld; it is a spiritual dimension, only accessible through spells. The entire plane and the demons within are shaped by the thoughts of humanity and all sentient species; if the good outweighs the bad, it becomes a paradise; if the the bad outweighs the good, it becomes hellish. In these trying times, evil is far more numerous than good, and the Underworld and its inhabitants reflect that; however, in the cesspit of evil there still remains some good spirits, but they are far weaker than their evil counterparts and both are vastly and massively outnumbered by their morally gray counterparts. The demons can take whatever form they choose, and the more powerful the Demon, the more it can affect mortals; Demons are divided by mortal scholars into Lesser, Normal, and Greater; Demons are born into a lesser status and gain in power as they feast on souls. Lesser Demons are numerous but weak; their mental power is on par with a normal person's; for every person, there are ten lesser demons. Normal demons have more power and are less numerous. Greater Demons have might unparalleled; they have no trouble enthralling even incredibly strong-willed humans; Greater Demons are often worshiped as Gods by mortals, and it is frankly not far off; in the Physical world Greater Demons can annihilate entire armies in the blink in of an eye... or turn the entire army into their mindless servants.
Demons all have some latent mind-control abilities over mortals; stronger demons have it over their fellows. Every subset of Demons approach control differently, as we will see. Demons feast on mortal souls, and become stronger as they do so; when the soul is consumed, the soul becomes absorbed by the Demon, living locked out from the world inside it, until eventually the mortal's mind is erased, and they become a thrall of the Demon, as their very essence is absorbed. Demons gain souls through several ways; their worshipers offer them freely through sacrifice, those mortals who attempt to control them may instead lose their souls; or, a Demon's thrall may instead slay many as offerings to their patron demon. Mortals often attempt to resisit a Demon's control; some succeed, and the Demon is forced to grant them what they wish; most, however, lose; their eyes roll back into their head as the enter a worshipful trance, chanting the Demon's name while bowing before them. When a Demon mentally takes control of a person, besting them in the game of willpower, the Demon may simply eat the person's soul, leaving them a mindless husk and servant of the Demon, a thrall, or the Demon may decide this individual will make a better offering of souls should they be allowed to live as their still free-thinking servant, binding their souls together. Most demons shy away from the binding of souls, however; when the souls are binded, the bind cannot be broken, and while the Demon can influence their mortal servant, their servant can influence and change them as well.

Let us look at the types of demons, and their respective ideas of effecting mortals.
Demons of War, Honor, Mercy, Pride, and Weaponry: These Demons are violent creatures; they have the most sway over the warriors of man kind. They take pride in combat. These demons are the most likely to soul-bind, not wanting to destroy a warrior's spirit, their greatest asset. When in the mortal world, they often take the form of warriors or beasts, or sometimes as weaponry, influencing greatly those who wield them. When attempting to control a mortal, they take a blunt approach; a clash of willpower, pure and simple; if they win, they eagerly take their new servants; if they lose, they graciously grant what the mortal wishes.
Demons of Love, Lust, and Greed: Seducitve and deceptive demons, these demons try to worm their way into the hearts of mortal; they take a form most attractive to their target, and using seductive rhetoric, calmly talk their way into control over the mortal; their twisted words and deception makes it hard to defeat these demons in will power, for even if you think they lost, they have won; use a sword instead
These are just two prime examples; there are countless demons of many types.

With the diversion to the underworld completed, let us now conclude our overview. The world is dominated by aristocrats and kings; slavery is common place. Tyranny is everywhere. Men die without ever knowing what they could accomplish; will you accomplish something? Will you make it onto the stage of history, forever remembered by Demon and Mortal? These are questions you must answer.

Character Application
I do not have a need for a formal application; I want detail of who this person is, their species, what makes them special, magical abilities (if any) and what equipment they have. About five paragraphs or more per character is suitable. Demon/Mortal pairs are accepted as any other individual character.