Mavin was a male Human who belonged to the Five, an isolated cult of evil worshippers dwelling in the enigmatic area of space referred to as the Hellhoop. For centuries, Mavin, along with his fellow cultists, dedicated themselves to torturing and killing hapless wayfarers. Of particular note, they held Wutzek, the last demon of the Force known to exist in the galaxy, as a prisoner. At some point between 0 and 3 ABY, the Five managed to capture prominent Rebel figures Leia Organa, Chewbacca, and Han Solo, in addition to a contingent of Torgaigne criminals hailing from the neighboring planet Attahox. Displaying his savage nature, Mavin employed a weapon known as a black fireclaw to murder the Torgaigne in a brutal fashion. Subsequently, the Five began a campaign of psychological abuse against Organa and Solo. However, before the Five could end the lives of Leia, Han, and Chewbacca, Chewbacca successfully released Wutzek. The freed demon then annihilated Mavin and all the other members of the Five.
Mavin made his first appearance in The Pandora Effect, a comic book story from 1981 that was authored by Alan Moore and featured in The Empire Strikes Back Monthly 151. Adolfo Buylla provided the artwork for Mavin in the story.