you had explored the lands of an ancient temple on a rainy night and had slain the lightning beast known as Nue. you then see that a door had opened for you via magic, and you went through. there was a one-eyed imp blocking the next door, and the Onmyo Mage known as Fuku.

"Greetings! My name is Fuku, and I am quite adept in Onmyo Magic. It is a pleasure to meet you."

she bows down, greeting you with a calm smile on her face.