Soul Harvester DemonsQuick Overview: Soul Harvester Demons are denizens of Multiple Layers of the Abyss and the takers of peoples souls. They can look like anything from the classic Red with wings, horns, and tails to almost human. Evil by any definition of the word they are all engaged in something called The Great Game. Any attempt to understand it or it's rules by non demons is nearly impossible.
Detailed Look: Soul Harvester Demons are entities of immense magical power that reside in the lower planes known as the Abyss. While the origins are shrouded in mystery their motives are nothing if not completely transparent. They want souls. The reason for this is more necessity than anything else. Soul Harvester Demons don't have souls of their own. The reason they attempt to gain your soul through contract and trickery is power. A soul can be obtained by killing the owner and ripping the soul from the body. However, this causes irreparable harm to the soul and robs it of some of its power. A soul given freely maintains its power and much much more.
As Creatures Devoid Of Souls, Soul Harvester Demons cannot normally manifest on the material plane. They must acquire powerful souls in order to be able to do so and then they must also find a way there from the Abyss. The loophole to this rule is a summoning. A sufficiently powerful magic user can summon a Soul Harvester Demon from the abyss and bind it to service. During this time the missing soul is replaced by the manna from the magic user. Thus it is a constant drain on magic users power to have a Soul Harvester Demon around.
Soul Harvester Demons also feed on souls as a form of sustenance. According to them souls have varying tastes. The very best souls are those whom are pure. Those who served good and justice whom were corrupted. Soul Harvester Demons will eat or take any soul however and will employ any tactic to get those souls.
Relations: Soul Harvester Demons don't have formal relations with any race. Most who would associate with demons view them as tools to be used. Strangely Soul Harvester Demons view all other races with that exact same point. To a Soul Harvester Demon, mortals are either food or a useful tool that can be used against another Soul Harvester Demon in the Great Game. To that end it is possible for demons to create offspring with nearly any mortal race. Soul Harvester Demons themselves have no gender although many of them have a form that they enjoy taking based off the male and female mortal forms. They believe that this form can be used as an advantage to befuddle and subject mortals of the opposite form.
Half-Soul Harvester Demons: As previously mentioned, Soul Harvester Demons are capable of producing offspring with nearly any mortal species. This can be as both the male end of the mortal species or the female end of the mortal species. Many women who are cursed to carry demon spawn generally do not survive the birthing process and the spawn is destroyed by others. However few do and raise their Half-Soul Harvester Demon children. Half-Soul Harvester Demons can be of any morality as they DO have souls. It is generally believed that the first Half-Soul Harvester Demon was an experiment by a Greater Soul Harvester Demon Lord to see if it were possible to fuse a soul to demonic essence. While the Half-Soul Harvester Demon had a soul the Lord was unable to figure out from whence it came and declared it a failure. Some Half-Soul Harvester Demons spend their time fighting the evil that made them. Yet others embrace this same evil. They are just a varied in morality and purpose as other mortals, however, much more rare to find.
The Great Game: All Soul Harvester Demons great and minor are engaged in something called The Great Game. The rules are unfathomable to mortals and the purpose more so. It is the tool by which Soul Harvester Demons measure their power and status against each other. The standings in The Great Game determine who has fist claim on evil souls unclaimed by deities that die of natural causes, who goes through a new portal to the material plane first, or even who may answer a non specific unnamed summons. It is the mechanism by which the universe, apparently, seeks to keep Soul Harvester Demons balanced against the rest and the past time which all Soul Harvester Demons engage in.