As always, the Encyclopedia Mythica provides the source material.
The Three Stooges (Daevas) of demons in Quest are minions of Dev, the war god.
Aesma is the demon of lust and anger, wrath and revenge. His wrath is mainly directed towards the cow (go figure). He is the personification of violence, a lover of conflict and war.
An ancient Persian demon of laziness who tries to prevent people from working.
An archfiend. Nanghaithya is the personification of discontentment.
Dev (the little devil) wants war to usher in Armageddon. Why? Because war is his thing and wiping out all humankind is on his to-do list.
To that end, he sends three daevas (demons, if you will) to turn Faiza’s companions on the quest to the dark side (sort of a Darth Vader thing).
Aesma appears to Parviz in the form of a bear with a serpent’s tail. Parviz was a slave and has a mile-wide chip on his shoulder. Aesma fuels that anger and convinces Parviz that the others are his enemies, not his friends. He’s told to wait for Dev to call him into battle. And, of course, keep his mouth shut about the little meeting.
He sends Buyasta in the form of a giant spider to Bahar, who has always dreamt of becoming a warrior. The demon takes advantage of that dream to make Bahar fall asleep (laziness) and dream of himself as a mighty fighter in a huge battle. The good part: Bahar is kicking major butt. The bad part: The butts he’s kicking are those of his best friends.
Nanghaithya has a little un-pep talk (he’s a voice-over character) with Harib claiming that his friends all laugh at him and only keep his company because his father is rich. The demon attempts to make Harib discontented with his relationship with the others. Harib, however, is having none of it. He’s the only of the three boys who stays true to Faiza.