Did your demons fall from grace, or were they always evil?

They are created inside/by their home planes, which are evil, so they are beings of evil.

My demons are a bit like Satan in the book of Job.
Essentially they are pious, but free-willed servants of the One God tasked with tempting the faithful. While their day job is inducing people to dick themselves over, they are genuinely good guys(beings?), who genuinely hope that their charges will reject their advances.
As is the case with all free-willed beings, some of them deviate from the will of the One God and try to enforce their own interpretation of divine law, which nearly always ends messily.
Sometimes they rebel properly, declaring a "fuck you" to the divine plan, which ends messily without fail

Cosidering God is a eldrich abomination and they are the only ones with any sort of vested interest in humanity, I'd say they yes.

You really should thank them, freewill is a gift given from knowledge and they gifted it to us.

As we stray further from the light of god we become masters of our own destiny, but also victims of his wrath (just like real life).

Demons are faithful lawful good servants of God who tempt mortals in order to test them.

amy demons are bron from concepts that managed to become physical beings from oversaturations of magic in places where emotions run rampant.

Magical wars spawn demons like crazy, and usually demons of hate, fear, sadness and apathy appear from those places. Orgies easily spawn succubi depending on the scale, and banks test employees by letting them into the vaults to see if they spawn greed demons.

All in all, mlst demons are pretty chill if they aren't spawned by absolutely negative feelings like hate, envy, etc. Sometimes though, those "evil" demons twist their concepts into ways that make them work well for the society, like envy assisting others to get whatthey want legally and admirably.

Their patron deities all got killed so they had to flee to hell where the asshole angels couldn't find them. They are as evil in the same proportion as the surface races.

Demons are supposed to be immature/young when compared to all the other divinities (angels, gods, souls, etc.)
So, they are as evil as the average child. Which is to say: very evil.

There are fallen angels but they aren't all that different in nature from non-fallen angels or evil deities.

>"Master" your own destiny
>By giving into vices and weaknesses
I chuckled.

I'm fond of classical Fuck-God's-Plan demons crossed with D&D Devils. They couldn't handle Heaven's arbitrary feelgood bullshit, so they became vehemently meritocratic and disciplined.

Hello Fair Folk.

I wonder if there's a way to do this well. Maybe occasionally one asshole will fight his way to the top of the asshole heap, and decide either he doesn't want all his fabulous prizes to get wrecked in the ensuing struggle, or that he doesn't actually feel happier for having climbed that particular mountain.

I haven't really settled on what my demons are. My devils, though, are essentially rogue ex-celestial intelligence agents.

Always.

I don't have demons of any kind. The only thing that even gets close is fae.

Depends on which type of demon.
The Hellish Princes are righteous yet cruel rulers, and are happy to help a human if it fits their interests.
Demon champions are pious servants of the rulers, so they model themselves after their masters.
Average demons, who are similar to humans, as they have free will, but since they can feel a wider range of emotions and think in ways that humans cannot, they're more likely to act in ways that may be seen as evil by humans.
And then there's the Abyssal Inhabitants, they're basically corrupted A.I.s created by either higher demons or occultists to serve some kind of purpose, but were later forgotten, abandoned or just went crazy and obsessed over their purpose to a dangerous degree.

I have demons as people who died filled with hate, or they were evil and lived in hell long enough to become demons.

But I made Balrogs into fallen angles.

Combination of both.

Demons spawned from the corpse of an ancient primordial beast/giant fucking worm designed to devour life on the world in order to keep raw magic/overpopulation in check. Demons crawl from the ancient worms blood, bones, skin, muscles, organs, etc. and each form personalities based around what body part they originated from. Later corrupt other beings, angels included, into demons as well.

There are several types of spirits in my setting that could be called demons.

Cacodaemons, also called Rakshasa or Yaoguai among other things, are evil spirits that are manifestations of hatred, cruelty and rage. They go around driving other creatures to acts of malice and then feed on the resultant energy.

Nightmares, also called Mara or Walriders, are personifications of fear. They come in numerous types that represent the fear of different subjects, there are nightmares that look like creepy dolls, men with chainsaws, zombies, ghosts, dogs, sharks, or anything else one might be afraid of. They mainly live in the dream world, but they can move through the aether like any other spirit and cause sleep paralysis or hallucinations. They sustain themselves by the fear they create.

Marids are beings from among the Celestial Choirs who split from their kin over a disagreement on interaction with humans. These beings are the ones that form contracts with humans, among them are the demons of the Ars Goetia like Stolas and Buer.

Outsiders are things from outside of time and space as it is understood. Whether they come from a parallel universe or are remnants left over from a universe that died before this one was born, it is impossible to tell. They are Lovecraftian horrors that are extremely unpredictable, and no two ware alike, but for some reason they are all attracted to Magi.

Demons are conquerors. They fuck shit up and rule by fear and violence.

Angels are liars. They show up in their resplendence and charm worship out of mortals with tricks and silvered words.

my demons were created by a dark god to harm mortals, and initially had no free will, but made a deal with a mortal king that resulted in not-tieflings and gaining overthrowing their master.

Yugoloths were always evil. Demons were largely always evil, though there are some fallen upper planar beings in there. Devils are exclusively either fallen upper planar beings, their offspring, or demons or yugoloths who have switched sides.

Although it's worth noting that some devils ended up as devils more for hanging out with the wrong sort of people than actually doing anything wrong, and didn't fall so much as saunter in a vaguely downward direction.

The devil fell, because he went into the time before creation and came out of it...wrong. Demons are all from then/there and have always been fucked up little shits, mainly due to their incomprehension of the concept of form.

Always evil. My demons are congealed human sin that's managed to claw it's way back to the surface and combine with a soul. Before that it's basically an ooze made of hate and illegal sex

My demons are ascended mortals

My demons are servants and spawn of the Elder Gods who hunt down and devour magic. Apparently souls are made of magic.