催眠隷姫

Niru lives his life as a slave. All of a sudden, a demon emerges before him.
“Though you may have been abandoned as an unwanted child, you are in fact the heir to the royal throne,” explains the demon. “How would you like to claim your revenge with my powers to manipulate the human mind?”

Niru signs a contract with the demon and obtains its powers. He murders his twin brother, the prince, and takes his place.
Then he proceeds to turn his hatred on his mother, the queen, and his sister, the princess.
What fate shall befall this man who wields these ungodly powers?