Meridiana

Meridiana was a succubus that Gerbert of Auralliac (946-1003), who became Pope Sylvester II (999-1003) supposedly made a pact with. She offered him sex, magical knowledge and money on the condition that he was faithful to her. He agreed and prospered rapidly becoming Archbishop of Rheims, Cardinal, Archbishop of Ravenna, and ultimately Pope. All the while, he kept Meridiana secret. Before his death, he confessed of his sins and died repentant.. This story was told by Walter Mapes in his De Nugis Curialium (Trifles of Courtiers)  en.wikipedia.org/wiki/Succubus