Oni
Oni are a giant race of demons living in Hell alongside succubi, usually 80-90' in height.
Physically, they can be described as more 'barbaric-like' compared to their succubi cousins, sporting large tusk-like fangs, sometimes red or blue skin, and wild, unkempt hair. They also possess horns, commonly claws, and muscled, sturdy builds. They have been known to have more monstrous qualities as well, though most you'll see with extensively grotesque features are actually invoking one of their abilities and don't actually look like that (and is most likely for their own amusement). Unlike their succubi cousins, oni do not possess wings or tails.
While succubi utilize their slender forms and sexual prowess to lure prey; their wits to climb the political ladder for influence and power... Oni do not.
They are infamous for their laziness and lack of ambition in the political hell hierarchy. There has never been an oni that held a particularly high amount of power and influence in Hell, but that's mainly just because they don't bother with the effort. Oni are usually content to pledge their loyalty to someone else, making some see them as little more than brutish minions. On the other hand, they are a great deal more trustworthy than the common succubus, and an alliance with one isn't likely to get you stabbed in the back later.
Oni aren't particularly good at using or learning magic. They do have a limited form-shifting magic that lets them take on a more monstrous form for a time, which they usually do to strike fear into their prey or potential enemies. Besides this, some oni might have some basic fire spells and such, and practice summoning. Like succubi, they do know dimensional magic in order to traverse the various planes.
Where their real ability shines is that oni are, in fact renowned, feared and respected for their ridiculous physical strength. In a war with heaven, the succubi might be the tacticians, powerful spellcasters and decent warriors, but oni are the ones that jump into the fray fearlessly, acting as a tank. In battle they impressively wield massive metal clubs called kanabō with surprising ease. In hell they carry these burdensome weapons on them most of the time, not wishing to be unprepared for a fight. For this reason most of hell's denizens don't bother them too much, especially when they're drunk, which is fairly often.
When oni are not serving as bodyguards or such, they may leave hell to visit other planes, including Felarya. When in Felarya their strength and endurance is decreased some, so they don't always carry their kanabō with them. When not acting out their duties, oni rarely pass up the chance to mess with people, and if one appears to a group of adventurers, it's just as likely to transform into a terrible monster just to scare them than to eat them (though sometimes both). Oni don't have a very good grasp of seduction tactics, and are fairly straightforward when it comes to hunting.
They usually aren't too quick to anger and don't have much of a temper to speak of. If you do challenge them, they'll fight back, however, often with overwhelming force. Some pit nagas have contracts with oni, and summon them as allies as with succubi. Unfortunately, the chance of the summoned oni actually being fully awake (despite carrying around a weapon for being prepared at all times) and simultaneously sober aren't very great.
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No, they aren't succubi, but as another demonic race, I figured this was the most appropriate place for the topic.