Info: Demon Guide/Reminder
Helped by the Frieren subreddit post listing off all the emotions demons feel and Frieren Wiki stuff.
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What they can feel:
Pride/Arrogance for their Magic.
Disgust/Anger, For those who mock their magic and beliefs/Concealing Mana.
Fear/Concern/Worry/Fear of death.
Excitement, Enjoyment, and Amusement, Especially over battles. (Qual firing out his magic, Aura showing off her mana)
Admiration/Recognition/Respect (Demons seem to respect the Demon King and other powerful demons, recognizing their power and efforts, this especially applies to Qual who seems somewhat revered by other demons like Lugner who look up to him for his dedication to killing magic)
Pain but it is numbed out.
Annoyance/Frustration.
Sadness/Sorrow/Despair. (Aura beheading herself)
Desire/Interest/Passion for Magic and obtaining power through it.
Degrees of Concern/Hope/Camaraderie? for their fellow demons/species (The Demon Seer wants to prevent demons from going extinct, Macht hoped the Seer wouldn't die)
Curiosity for things that interest them (Solitar's and Macht's fixation on humans)
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They don't feel:
Empathy. At least various degrees of it.
Malice, at least generally speaking.
Guilt.
Selfless Love.
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Personality
While demons have been shown to feel emotions, they do not feel the same emotions as humans do, and as a result, are incompatible with human ideas of morality. Demons look down on humans and only view them as prey. Demons mock human empathy and think they are weak, which is why they constantly underestimate mankind. They are deeply proud of their mana levels, and due to the power-based hierarchies they form, they will not and cannot conceal their mana for long periods. Even temporarily concealing it to avoid detection—something which any demon can do according to Lügner—is considered to be inappropriate in a battle between mages.
Can't feel almost any emotions just enough to deceive humans with the only exception of extreme cases. Only faking emotions to trick and deceive humans.
Close to the general definition of a psychopath. Don't instinctually care for many things besides themselves/other demons.
Not driven by bloodlust, malice, or hatred. Just self-interest. They are indifferent to what's right or wrong or don't know what's right or wrong. They don't feel empathy but somewhat understand it and use the empathy of others to fool them.
Kills humans with indifference like killing an ant. Like feeling nothing when you kill something lower than you. They don't feel any guilt towards the people they kill.
Demons feel little and to no emotion but one emotion that they prominently do feel is pride. Pride in their abilities as a mage. Pride in their magic. They challenge other human mages head-on because their ego in magic. Confident in their skills.
Social Hierarchy
For demons, strength determines one's position in their social hierarchy, which can be assessed at a glance by reading a demon's mana. Because mana to demons is what status and assets are to humans, demons cannot imagine constantly limiting their mana, as it is akin to their very dignity. They in turn expect their enemies to not hide theirs, either.
Personal Relations
Demons prefer to be alone and avoid contact with other members of their species beyond the necessary. They only form groups so that they can fight against mankind, refusing to form any deep bonds with each other. It seems unusual for demons to show a deep sense of loyalty to another or to show a desire to avenge a fallen comrade, some demons go so far as to show indifference towards the idea of their entire species being in danger.
Due to their individualistic nature, the concept of family is foreign to them, and they will often abandon their children once they are born. They also seem to lack the notion of romantic relationships, as no demon couples have ever been seen.
Weekly Power Status
-- Power
Ranking 
-- Power
stone