Ragishss Cryhausen

Ten years prior to the story in Rance 2, Ragishss was a mage who opened a cram school that taught the ways of magic. Among the students, there were four girls who he did consider as having the potential to become great magicians who are able to protect Kathtom in the future. However, after ten years, the girls suddenly rebelled against Ragishss and killed him.

Rance 2
Player can access his house and have a chat with him at the first chapters. He appears as a ghost who claimed himself to be the town's protector, though he also claimed that he doesn't have any power to attain his form forever.

Ragishss stated that the four girls stole his rings to increase their magical powers and also killed him in the process.

Spoilers ahead.

It's later revealed that the main villain is actually Ragishss himself. The rings which Ragishss mentioned aren't just able to give boost to magical powers, but they can also steal magic power from virgin sorceresses and drive them insane little by little. After collecting a total amount of magic power equal to that of of 40 maidens, the rings are able to grant a magician unlimited power. Knowing Ragishss's plan, Masou Shizuka, who was the strongest and considered as the leader of four maidens, rebelled against him to prevent his plan from succeeding.

In the last chapter, or more precisely after Rance collects all of the rings,? Cith, who is currently possessed by Ragishss, steals the rings from Rance to possess unlimited magic power and becomes the final boss that Rance must beat, with the help of Sill, Shizuka, and Maria.