In a remote village, in a fantasy time, a young man explores an old book of sorcery he found in a locked cabinet. The book was the legacy of a long dead sorcerer, and now he too attempts to learn the secret magic held inside its pages. As he turns the various chapters, he finds one that talks about demons from the underworld. There, he finds a spell that claims to be able and bring a succubus from the underworld, to serve whoever summons her, and be a loyal servant. These succubus are known to be incredibly beautiful and very powerful, and could be used for both personal pleasure, and to help the sorcerer gain power over others.
The description is simply too good for the young man to pass up, and he quickly draws up the correct glyph on the ground, and recites the spell. Unfortunately for him, he neglected to read the whole chapter, especially the part about how a succubus is also very deceitful, and that another spell has to be used right away in order to bind them to you. As he casts the summoning spell, he achieves success, and a beautiful young succubus appears. At first, she appears disoriented and confused, because she happened to have been sleeping in the underworld. The apprentice sorcerer thinks that means she's under his control, but the truth is she is completely free.
Seeing what had happened, Fael, the succubus, decides to have some fun. She plays the role at first, and pretends that she's under his control, doing everything he wants, satisfying his most private desires. Once she knows enough about him and what makes him tick however, suddenly she turns the tables, and overpowers him, showing how he was never in control, and how he's now her pet. But her ambition doesn't stop there. Soon, she humiliates him in front of the whole village, and forces him to betray the villagers in order for her to reign over all of them. The young man has no choice but to obey the wild and unbound succubus...
For this RP I'm thinking of the story starting as the summoning takes place, and I will play Fael who will pretend the spell worked, and be in the man's control, until she decides to turn the tables and start abusing him instead. Then, she will humiliate him in front of other villagers, and force him to do everything she wants in her mad grab for power.