In Purgatory, every succubus who has reached the fifteenth anniversary of their birth will be sent to the succubus academy "Malac" by their family or local institution for education.
In the branches named after the Seven Deadly Sins, the succubi are sorted into their respective branches according to their inner nature: the little succubi who like "sleeping" are assigned to the "Sloth" Academy, those who like "sweets" are assigned to the "Gluttony" Academy, and those who want to bathe in gold coins are assigned to the "Greedy" Academy...
Lucretia, the proud succubus princess who was given high hopes by her family, has a beauty and intelligence that makes all demons ashamed. She has a burning ambition to become a famous "big devil" like her ancestors and have her name engraved on the catalog of "History of Purgatory - Contemporary Chapter".
"Anger", "greed" or "pride"? It doesn't matter which one, she will do her best.
Until that day, the machine that detects the nature of the succubus, the magic mirror that had no idea how much wine was drunk last night, after flickering for a few times as if it malfunctioned, weaved this magic text in front of the teachers and students of the school:
"... Nature: pure."
Purpose: To bring a smile to every day's life