Adopt from  minsukyou
I decided to take a demon from Ars Goetia here too.
"Gremory is the 56th demonic spirit of the Ars Goetia that was summoned by King Solomon and rules as an Archduke of Hell."
"Gremory is a strong and great Duke of Hell that governs twenty-six legions of demons. She tells all things past, present and future, about hidden treasures, and procures the love of women, young and old, but with a bias towards maidens. Her demonic manifestation could thus be the personification of such an attribute. As with the rest of her kind, Gremory is born genderless but would usually take the form of a female.
She was raised by the Great King Paimon and has sworn absolute loyalty to him. She is said to sometimes turns into an ugly woman to test her summoners. Even as a demon, she was sometimes treated as the goddess of the moon. Once summoned by the dark magician Gebel, this demon oversees one portion of the castle he created."