Disgaea D2

They are widely regarded as one of the highest classes of demons in the Netherworld. They are small in number, but their strength is the envy of most demons. They are feared throughout Celestia, as well as in the Human World. However, due to their fame, there are many spells to summon them, and many books about how to deal with them.

Researchers have spent years studying Slumber Cats, but their origin still remains a mystery. They have many fans in the Netherworld, due to their cute cry and soft fur, and many are actually kept as pets. Although they are very affectionate, they are always looking for a chance to overtake their owners, so they make dangerous pets.

Originating from microscopic sea animals, Sea Angels came into existence due to polluted waters. Their bodies are semi-transparent. They are shy and cowardly, and usually travel in large groups. They usually stay underwater except to feed. When they eat, they release tentacles from their heads, grab their food, and slowly pull it back into the water.

Succubi consist solely of women. They make their living by seducing men into depravity. Contrary to their sexy appearance, they are very adept at fighting, and it is highly debated whether resisting them would do any good. All the other female classes hate Succubi, except Nekomatas for some reason.

Living Armors are unique in that, they'd rather fight fair and adhere to the rules of chivalry. This is because they are not intimidated by anyone. They are adept with the sword, and higher ranking ones can slice a dragon in half with a single swing. Since they share many of the same philosophies, they have good relationships with Samurais.

Of all demons, these are probably the most mysterious. Researchers can't come to a consensus about them, but one theory is that they are human souls that came to the Netherworld, but failed to become Prinnies. They are the most abundant class of demons in the Netherworld, but since they are basically just weak souls, they gather together in big groups.

Very rare dragons that look like sharks. There are very few of them in the Netherworld, and they are thought to be an alien species from a different Netherworld. They are very aggressive and love to fight. Only the strongest warriors should fight them. They can live on land or in the water, but since they don't like being dry, they prefer the water.