Rika's hobby is reading. Recently, she has been particularly fond of the history of torture in the Middle Ages, and has been devouring it. While reading in the usual park after school, Rika finds herself lost in the story. Dream? Reality? When she wakes up, her hands and feet are bound with heavy iron shackles, and she is imprisoned in a state where she cannot move her body freely. A man dressed in black appears and materializes Rika's delusions and desires. At first, Rika feels fear and shame, but gradually she loses herself in the men's training and indulges in pleasure.