Fallen angels are angels who rebbeled against God out of pride and wanting to be like Him. God did not destroy them, but permit them a scope of limited activity.
Below are the three classes of the Demonic hierachy. N.B all the chief of the nine choirs of angels are fallen.
THE FIRST HIERACHY
The first hierachy includes angels from: The Seraphims, Cherubims and Thrones.
1.BEELZEBUB: Beelezebub was a prince of Seraphims just below Lucifer. He along with Lucifer and Leviathan were the first three angels to fall. Beelzebub now a fallen angel, tempts people with pride and is been opposed by St. Francis of Assis.
2.LEVIATHAN: Leviathan was also a prince of Seraphims, the ringleader of heretics. Opposed by St.Peter.
3.ASMODEUS: Asmodeus was also a prince from same order with Laviathan and Beelzebub, he is the prince of wantoness and is opposed by St. John d Baptist.
4.BALBER: a prince of Cherubims, tempts people to comit homicides, to be blasphemous, contentious and quarrelsome. Opposed by St. Barnabas.
5. ASTAROTH: once a prince of Thrones, now tempts people with laziness and idleness. Opposed by St. Bartholomew.
6. VERRINE: also a prince of Thrones, tempts people with impatience, opposed by St. Dominic.
7. GRESSIL: third prince of Thrones, tempts with impurity and uncleaness; opposed by St bernard.
8. SANNEILLON: was also a prince of Thrones, now tempts people with hatred; opposed by St. Stephen.
THE SECOND HIERACHY
The second hierachy includes angels from: Dominions, Virtues and Powers.
9. CARREAU: a one time prince of Powers, now fallen and tempts people with hardness of heart; opposed by St. Vincent and Vincent Farrer.
10. CARNIVEAN: also a prince of Powers, tempts people with obscenity; opposed by St.john d Evangelist
11. OEILLET: a prince of Dominions, tempts people to break the vow of poverty; opposed by St. Martin
12. ROSIER: second prince of Dominions, tempts with secyal impurity; opposed by St. Basil
13. BELIAS: a prince of Virtues, fallen and tempts women to gossip during mass and men with annoyance; opposed by St. Francis d Paul.
THE THIRD HIERACHY
This hierachy includes angels from: Principalities, Archangels and Angels
14. VERRIER: a prince of the order of Principalities, now tempts people with disobedience; opposed by St. Bernard
15. OLIVIER: Olivier was onece a prince of the order of Archangels, now he tempts people with cruelty and mercilesness towards the poor and he is opposed by St. Lawrence.
16. LUVART: Luvart is the only fallen angel from the order of Angels
Though there are still seventy (or more) angels that fell alongside Lucifer after the rebbel, these are the top angels because they were all chief and or second in commands in the nine choirs of angels. The order of Principalities played a major role during the rebbel. Dominions, Cosmological powers, Powers and Thrones also took sides with Principalities. Some angels were also expelled from the heavens after the incident recorded in the book of Origin chapter 6.