Majin

Majin (魔人), also known as Magic-Born, is a catchall term for intelligent Monsters. They can be born naturally, be the result of monsters that have undergone mutation, or evolved from already intelligent non-magical beings that have undergone monsterization.

Most Majin have reproductive ability, but usually only within their own subspecies. In their upper social castes exist Greater Majin such as Giants, Vampires, Harpies and other longer-lived species all equally capable of having offspring, although they rarely do so, since their immense Magic Power causes them to be nigh-immortal, obviating the need to leave descendants.

Demonoid
Demonoid (人魔族) is a generalized term used to refer to Majin who were originally Humans, but have had their body mutated by magic to become monsters.

Greater Majin
Greater Majin (上位魔人) is a general term used for Majin who are Over A Rank. They hold power unimaginable to a normal person, usually being found in service to one Demon Lord or another as apart of their elite troops. In some areas, they are even worshipped as Local Gods.

Examples include Gelmud before their naming spree and Geld in their Orc Lord state.

Sub-Demon Lord Level
Sub-Demon Lord Level (準魔王級) is a general term given to Majin who have surpassed simple Greater Majin in power and reached Special-A Rank. Although their strength is still a far cry from Demon Lord Level, they're powerful pawns for the Demon Lords, with them usually taking thorough preparations in order to either take them down or bring them to their side. For Majin of this level it isn't strange for them to have powerful minions in the form of Greater Majin and Greater Daemons assisting them in their schemes, allowing them to potentially take down an entire nation with thorough preparation.

Examples include the Orc Disaster Geld and the Three Beastketeers prior to receiving gifts from Carrion's Harvest Festival.

Demon Lord Level
Demon Lord Level (魔王級) is a term used to refer to Majin that have strength comparable to a Demon Lord but aren't themselves officially recognized Demon Lords. Majin of this level usually have one or more Sub-Demon Lord Level subordinates and dozens of Greater Majin under their control. It isn't unusual to find them in control of a large area of land comparable to a small nation.

Examples include Charybdis and Rimuru Tempest prior to undergoing the Harvest Festival and joining the Octagram.