Satan was a demon created from Lucifer's wrath. Satan loves books and cats. Satan is a demon who is considered the Avatar of Wrath. 

A lover of books and cats.

He has a gentle personality and is always smiling, but also has a sharp intuition. He is hopeless with technology.

A smart, yet gentle angel. 

The youngest, cheekiest, and most cunning of the demon brothers. 

A demon who loves to take naps and sleep. 

Diavolo is the ruler of all demons, and all who reside in the Devildom know of his name. Despite being one of the most powerful demons in the Devildom as well as the Future King, Diavolo takes on a surprisingly fair and compassionate, if not joyous, attitude at almost all times. Diavolo proves to have much more wisdom than his cheerful demeanor suggests.

The optimistic demon ruler of Devildom. 

A growing demon who is always eating something. He loves his younger twin brother Belphegor.

A demon who is always hungry. 

The scummy second-born who is greedy for all the money in the world. The witches are his big weakness.

A greedy scumbag who wastes money. 

Known in the Devildom for being Diavolo's close friend and right-hand man. He is the oldest of the 7 demon brothers. He keeps the brothers together, by force if necessary. Lucifer is the Avatar of Pride and is the eldest among the seven demon brothers.