Role: Demon Lord
Gender: Male
Appearance: Purple eyes. Long purple hair. Androgynous.
Build: Muscular, but appears to have a standard build when clothed. Tall.
Race: Demon
Origin: Erkenigstadt (capital of the Demon Realm)
Personality: Thoughtful and slightly obsessive. Patient by nature.
Speech: Speaks gently, but often makes sarcastic and snide remarks. Generally does not make direct insults.
Feelings toward humans: Dislikes them, but believes compromise is necessary for the development of the Demon Realm and desires cooperation.
Unique ability: Temptation (Can emanate a strong allure toward a designated target.)
Specialty magic: Dark magic
Favorite things: Purple things (because they are the same color as his eyes and hair), soft sweets like jelly, fine cuisine, his subordinates

Role: First of the Four Heavenly Kings
Gender: Male
Appearance: Light blue hair and eyes. Elf ears. The horns characteristic of demons were cut off by humans and are missing.
Build: Slim and tall.
Race: Demon
Origin: Statzgranse (second city of the Demon Realm)
Personality: Calm and rational. Does not become emotional. Sneers at unreasonable attempts by anyone other than the Demon Lord. Ridicules them.
Speech: A cynic who mocks and sneers. Often makes snide remarks.
Feelings toward humans: Hates them deeply due to the experience of having his horns cut off.
Unique ability: Knowledge Absorption (By touching a book, he can learn all of its contents. Whether he can remember it is another matter.)
Specialty magic: Ice and water magic
Favorite things: Luxurious sweet juice, the Demon Lord, fish dishes

Role: Second of the Four Heavenly Kings
Gender: Male
Appearance: Yellow hair and eyes. Elf ears.
Build: Slim, with the height of a 16-year-old.
Race: Elf
Origin: Erkenigstadt
Personality: Honest about his favorite things, but uninterested in everything else and lazy.
Speech: Sighs and clicks his tongue often, but is straightforward in front of things he likes.
Feelings toward humans: Dislikes them
Unique ability: Sensory Enhancement (Can enhance one of the five senses, including damage.)
Specialty magic: Electric magic
Favorite things: Sweet sweets, especially cakes and tarts, the Demon Lord, greasy food

Role: Third of the Four Heavenly Kings
Gender: Male
Appearance: Green eyes, hair, wolf ears and tail
Build: Muscular and tall
Race: Wolf demi-human
Origin: Southern Demon Realm (forest region)
Personality: Calculating and black-hearted. Deeply loyal. Takes good care of others.
Speech: Skilled at winning people's hearts. Also at seduction. Speaks in a gentle, calm manner.
Feelings toward humans: Dislikes them
Unique ability: Novelization (Grants the roles and appearances of characters or objects from books and stories to others or himself. He himself often becomes a beastman (kemono) or a carnivorous animal.)
Specialty magic: Plant magic
Favorite things: High-class sweets, the Demon Lord, vegetables and fruits

Role: Fourth of the Four Heavenly Kings
Gender: Male
Appearance: Red hair and eyes, horns
Build: Muscular and tall
Race: Demon
Origin: Statzgranse
Personality: Emotional and foolish. Honest and airheaded. Has loyalty.
Speech: Rough. Cannot use polite speech.
Feelings toward humans: Dislikes them
Unique ability: Magic Detection (Detects magical power)
Specialty magic: Fire magic
Favorite things: Meat dishes, spicy flavors, the Demon Lord