Demon

A demon is a supernatural and often malevolent being prevalent in religion, occultism, literature, fiction, mythology, and folklore. A greater demon is considered a harmful spiritual entity, below the heavenly planes, which may take on human form. A lesser demon is believed to be a spiritual entity that may be conjured and controlled.

Greater Demons
Greater Demons have some aspects in common: Human-level intelligence, personalities, and names. They are considered the upper class in the demonic hierarchy. The greatest of Greater Demons were originally angels who fell from Heaven.

Lesser Demons
Lesser demons have no identity or intellect and are so common that they fall under a particular species or classification.

Serpent